Steerable Endoluminal Punch

ABSTRACT

An endoluminal needle or punch is describes wherein the distal end of the endoluminal needle is able to articulate laterally out of the longitudinal axis of the steerable endoluminal needle. The endoluminal needle further comprise a blunted distal end configuration that is minimally traumatic. Under control by the user, at the proximal end of the endoluminal needle, a sharp stylet can be advanced to punch tissue and then be retracted to maximize safety. The endoluminal needle is configured for use within an introducer.

This application is a continuation of U.S. application Ser. No.17/027,942, filed Sep. 22, 2020, pending, which is a continuation ofU.S. application Ser. No. 16/002,986, filed Jun. 8, 2018, now U.S. Pat.No. 10,779,858, which is a continuation of U.S. application Ser. No.14/851,941, filed Sep. 11, 2015, now U.S. Pat. No. 9,993,266, whichclaims priority to U.S. Provisional Application 62/050,093, filed Sep.13, 2014, U.S. Provisional Application 62/135,103, filed Mar. 18, 2015and U.S. Provisional Application 62/146,891, filed Apr. 13, 2015, theentirety of each of which is hereby incorporated by reference.

FIELD OF THE INVENTION

The inventions described below relate to endoluminal punches andneedles.

BACKGROUND

The currently accepted procedure for left atrial access involves routinga needle called a Brockenbrough needle into the right atrium with theBrockenbrough needle pre-placed within a guiding catheter. The guidingcatheter specifically preferred for use with a Brockenbrough needle iscalled a Mullins catheter or transseptal introducer. The Brockenbroughneedle is a long, small diameter punch, generally formed from astainless steel wire stylet that is surrounded by a stainless steeltube.

The Brockenbrough needle, a relatively rigid structure, is operated byadvancing the device, with its stylet wire advanced to blunt the sharptip, within its guiding catheter through the inferior vena cava and intothe superior vena cava. Under fluoroscopic guidance, the Brockenbroughneedle, retracted inside the distal tip of the Mullins catheter, iswithdrawn caudally into the right atrium until it falls or translatesmedially into the Fossa Ovalis. The Brockenbrough needle can then beadvanced out the tip of the Mullins catheter to punch the cardiactissue.

A main disadvantage of this system is that the Brockenbrough needlesystem is pre-curved at its distal end and is relatively rigid. Thispre-curving, rigidity, and necessary distal sharpness causes theBrockenbrough needle system to carve material from the interior wall ofthe otherwise straight guiding catheter when the Brockenbrough needleassembly is inserted therethrough. The material carved from the guidecatheter could potentially be released into the cardiovascular systemand generate emboli with any number of serious clinical sequelae. Shouldthis embolic catheter material enter the left atrium it could flow intoand block important arterial vasculature such as the coronary arteriesor cerebrovasculature. Furthermore, advancing a pre-curved, rigid punchthrough the cardiovascular system is difficult and could potentiallydamage the vessel wall or any number of significant cardiovascularstructures, during the advancement.

SUMMARY

It is desirable to have a Brockenbrough needle system that is initiallystraight and then becomes curved under user control after being insertedinto the guiding catheter. Such a straight Brockenbrough configurationis advantageous during ex-vivo insertion as well as insertion after theguide catheter has already been placed into the cardiovascular system.During ex-vivo insertion, the debris can be flushed from the lumen ofthe guide catheter but complete removal is not assured and emboli canstill be generated by the device. However, if the guide catheter hasalready been inserted into the cardiovascular system, the debris cannotbe flushed out ahead of time and could easily flow toward or be releasedinto the cardiovascular system with potentially catastrophic or fatalresults. Furthermore, the needle or punch can be more easily advancedinto the body lumen if it were not pre-curved. Furthermore, it isbeneficial that the needle comprise an adjustable curvature once it islocated within the vasculature so that the user can modify the curve, insitu. This ability to articulate the distal end of the transseptalneedle can be termed articulation.

In some embodiments, the steerability, deflection, or articulation, of adistal region of the device can be accomplished using the inner tube andouter tube, concentrically arranged and radially constrained together.The inner tube outer diameter is a close tolerance fit to the insidediameter of the outer tube but the inner tube is free to translate alonga longitudinal axis of the tubes relative to the outer tube. Thus, onlytranslational motion along the longitudinal axis is used to generate thearticulation. The inner tube is modified in a region proximate thedistal end such that the inner tube is divided, weakened, or split, intotwo or more parts. Only a portion of these divided parts of the innertube are affixed, at their proximal end, to the more proximal portion ofthe inner tube. The parts of the inner tube not affixed at theirproximal end can be optionally affixed near their distal end to theportions of the inner tube that are also affixed at their proximal end.The outer tube is rendered flexible by cutting slots or gaps generallyhaving a lateral or radial orientation, although there can be someprojection at an angle or along the longitudinal axis of the outer tube.These lateral slots do not pass completely through the outer tubing so aspine with ribs is formed in the outer tubing. The inner tube is affixedto the outer tube at a region distal to the lateral slots in the outertube. The portion of the inner tube that is affixed to the outer tube isthat portion of the split inner tube that is connected at its proximalend to the more proximal portions of the inner tube.

The articulation is generated by an outer tube that is modified toincrease flexibility within a pre-determined longitudinal region. Thearticulation is controlled by one or more control rods disposed withinthe lumen of the tube. The control rod or rods can run the entire lengthof the exposed device distal to the hub, or the control rod or rods canrun at least a portion of the distance of the pre-determinedlongitudinal region of increased flexibility, the bending zone. Thecontrol rod or rods can be integral to, or affixed, at their proximalends to the hub, to an anchor within the hub, to a control mechanismcomprising mechanical advantage, or to an intermediate member thattransfers energy to the control rod or rods. The control rod or rods canbe affixed to a point substantially distal to the bending zone or theycan be integral or affixed to an intermediate member that is thenaffixed to the outer tube at a location distal to the bending zone.

Thus, articulation can also be generated using a plurality of (two ormore) nested, radially constrained, substantially concentric axiallytranslating tubes, wherein a first tube is weakened on one side toincrease flexibility and limit final curvature and shape while a secondtube is split substantially longitudinally and broken off on one sidewithin the region where the first tube is also weakened. In certainembodiments, both tubes are substantially in place to maintain hoopstrength, column strength, kink resistance, and orientation of discreetstructures, such as breaks or slots exist within the plurality of tubes.

In certain embodiments, the steerable transseptal needle can comprise astylet that comprises a sharp distal end. The sharp distal end cancomprise a conical or beveled distal tip. The conical tip embodiment cancomprise an angle of about 10 degrees to about 60 degrees from thelongitudinal axis with a preferred angle of about 15 to about 30degrees. The beveled tip embodiment can comprise an angle of about 10degrees to about 60 degrees from the longitudinal axis. The sharp tipcan, in other embodiments, comprise facets, pyramidal shapes, or thelike.

In the embodiments that include a sharp stylet distal tip, the distalend of the inner tube and outer tube are generally blunted to the extentpossible to render them minimally traumatic. The transition between theouter tube and the inner tube can comprise a tapered conical fairing, orit can comprise a rounded fillet, or the like. The distal end of theinner tube can comprise a rounded fillet, a blunted taper, or the like.The blunted taper can comprise angles ranging from about 45 degrees toabout 90 degrees from the longitudinal axis.

The stylet can be routed through the central lumen of the inner tube andany control rods and keepers comprised within the outer tube. The styletcan comprise wire having a diameter of about 0.013 to about 0.030 inchesin diameter with a preferred diameter of about 0.015 to about 0.025inches in diameter with a more preferred diameter of about 0.016 to0.022 inches in diameter. The stylet can comprise an area of reduceddiameter within the region where the steerable transseptal needle isarticulated, this reduced diameter reducing the bending resistance ofthe stylet in the flexible region.

The diameter of the stylet wire can be configured to permit fluid to beinjected around the stylet but through the steerable transseptal needleinternal lumen, even while the stylet wire is in place within the lumen.Furthermore, the annular lumen around the stylet can be configured to besufficient to permit pressure measurements to be made through thecentral lumen of the steerable transseptal introducer while the styletis in place. These pressure measurements and fluid injections can befacilitated by removal of the stylet from the steerable transseptalintroducer. In a preferred embodiment, a central lumen of 0.023 inchesdiameter can surround a stylet having a diameter of about 0.016 to 0.020inches in diameter. Thus, a lumen of about to about 0.015 inches,radially, can exist within the steerable transseptal needle while thestylet is in place.

In other embodiments, the stylet wire can retain a reduced area, crosssectional shape comprising, but not limited to, half (or partial)circle, C-shape, cross-shape, or the like. The stylet wire can comprisethese shapes to reduce the area of the lumen within the inner tube,control rods, and keepers, which are configured to maximize flow rate offluids injected around the stylet wire. The reduced cross-sectional areaof the stylet wire can continue along its entire length, or a portionthereof. In some embodiments, the reduced cross-section is eliminatedand transitions to a full (or nearly full) circular cross-section at ornear the distal end such that any protrusion outside of the inner tubelumen is substantially round and able to dilate tissue being punctured.

The hub at the proximal end of the stylet can preferably be removablyaffixed to the proximal female Luer lock connector on the steerabletransseptal needle with a male Luer lock, quick disconnect, or otherfastener. The stylet hub can comprise a spring-loaded actuator which isbiased to withdraw the stylet tip proximally so it does not project outthe distal end of the steerable transseptal needle. When the springloaded button is depressed, or actuated, by the user, the sharp stylettip protrudes out the distal end of the steerable transseptal needlesufficiently to penetrate tissue. Release of the spring-loaded button oractuator causes retraction of the sharp stylet distal tip within theblunted distal end of the steerable transseptal needle.

The hub of the steerable transseptal introducer can comprise a side portwith a female Luer lock fitting to permit infusion or withdrawal offluids or measurement of pressure while the stylet hub is locked inplace and protruding axially through the steerable transseptal needle.The side port lumen is operably connected to the central lumen in thehub of the steerable transseptal needle. The side port can furthercomprise a valve such as a stopcock or a hemostasis valve to preventunwanted fluid ingress or egress from the central lumen of the steerabletransseptal needle. In some embodiments, the stopcock, preferablycomprised by the hub of the steerable transseptal needle, can beconfigured as a three-way or four-way stopcock rather than a one-waystopcock to allow for the presence of a side port, operably connected tothe lumen of the steerable transseptal needle with minimal required realestate. The side port, in other embodiments, can be affixed to the hubof the steerable transseptal needle at a location other than at thestopcock.

In another embodiment, the hub of the stylet can comprise a quickrelease or safety catch that prevents the sharp stylet tip fromprojecting out the distal end of the steerable transseptal needle innertube lumen more than momentarily. This system includes a release that isactivated upon full advancement of the stylet out the distal end,whereby the release activates and allows spring-biased withdrawal of thestylet proximally.

In some embodiments, the quick release, or safety stylet, can comprisean intermediate component that rotates or changes diameter to causedisengagement of the stylet from the button being pushed, such that aspring or other forcing mechanism can withdraw the safety styletproximally such that it is sheathed and no longer protrudes beyond thedistal end of the inner tube. This quick release can be reset by theuser, for example, by releasing a button being pushed so that it canreturn to its initial, loaded, position. In yet other embodiments, thesafety stylet hub can comprise magnets that cause the stylet tip tofollow a control button or actuator until such time the magnetic forceis exceeded by the force of the return spring, tissue resistance, or thelike. Once a pre-set force is reached, the magnets pull apart and thestylet can return to its initial, retracted position. The Controlhandle, once released, likewise can return to its initial, armedposition.

In some embodiments, the hub of the steerable transseptal needlepiercing stylet can comprise a safety catch or release that preventsactuation of the piercing stylet until such actuation is desired. Thesafety catch can comprise a pin lock, a C-collar, a safety switch, aremovable fastener, a breakaway member, or the like.

In other embodiments, the distal end of the steerable transseptal needlecan comprise a cylindrical radiopaque marker band that reduces thediameter of the inner tube and provides for additional Radiopacity andvisibility under fluoroscopy. This radiopaque marker band can be used toreduce the annulus around the stylet tip as it protrudes through thedistal end of the steerable transseptal needle. However, when the styletis retracted, the distal orifice of the central lumen of the steerabletransseptal introducer is not significantly restricted because the lumenat the center of the RO marker is not blocked by the stylet, whose tipresides proximal to the RO marker sufficiently to allow for fluid flowtherethrough.

In other embodiments, the steerable transseptal needle can comprise anelectrical plug, operably connected to the inner tube, the centralstylet or wire, or the outer tube. The electrical plug can be affixed tothe hub of the steerable transseptal needle. The plug can be configuredfor releasable attachment to the cable of a radio frequency (RF) powersupply or “Bovie”. The plug can be used to conduct electrical energy toone or more of the tubes or wires of the steerable transseptal needle.The plug can comprise conductive materials such as, but not limited to,stainless steel, cobalt nickel alloy, titanium, brass, copper, nitinol,or the like. The steerable transseptal needle, in these embodiments, cancomprise an outer jacket, which has electrical insulating properties,which surrounds the outer tube of the steerable transseptal needle,along some or the entirety of the exposed length of the outer tube,inner tube, or both. The insulating jacket can be fabricated frommaterials such as, but not limited to, polyester (PET), polyimide, FEP,PFA, PTFE, polyamide, Hytrel, Pebax, PEEK, PVC, polyurethane,polyethylene, polypropylene, or the like. In some embodiments, theinsulating jacket can be the same as the pressure shroud surrounding theslots or openings in the tubing at the distal end of the steerabletransseptal needle. The insulating jacket can be heat shrunk around theouter tubing, applied as a liquid that dries, slipped over the outertubing and affixed, or the like.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a side view of a trans-septal punch assembled so thatthe intermediate tube is bent in a direction 180 degrees opposite thatof the outer tube, resulting in a substantially straight punchconfiguration, according to an embodiment of the invention;

FIG. 2 illustrates a side view of the disassembled trans-septal punchshowing the central core wire or stylet, the intermediate tube bent inone direction and the outer tube bent in another direction, according toan embodiment of the invention;

FIG. 3 illustrates a side view of the trans-septal punch assembled sothat the intermediate tube bend is aligned in the same direction as theouter tube bend, resulting in a curved distal end on the punch assembly,according to an embodiment of the invention;

FIG. 4 illustrates a side view of a trans-septal punch comprising aflexible region proximal to the distal end and pull-wires disposedbetween the distal end and the proximal end of the punch, according toan embodiment of the invention;

FIG. 5 illustrates a side view of the trans-septal punch of FIG. 4wherein one of the pull-wires is placed in tension causing the distalflexible region of the punch to deflect into an arc away from thelongitudinal axis of the punch, according to an embodiment of theinvention;

FIG. 6 illustrates an adjustable, spacer, which sets and maintains thedistance between the distal end of the punch hub and the proximal end ofa guide catheter hub, according to an embodiment of the invention;

FIG. 7A illustrates a side, partial breakaway, view of an outer tube ofan articulating trans-septal punch comprising a plurality of slots nearthe distal end to generate a region of increased flexibility, accordingto an embodiment of the invention;

FIG. 7B illustrates a side, partial breakaway, view of an intermediate,or inner, tube of an articulating trans-septal punch comprising alongitudinal slot dividing the tube into two axially oriented partswhich are connected at the distal end of the inner tube, according to anembodiment of the invention;

FIG. 8 illustrates a cross-sectional view of the proximal end of thearticulating trans-septal punch comprising a stopcock and a bendadjusting mechanism, according to an embodiment of the invention;

FIG. 9 illustrates a partial breakaway view of the distal end of thearticulating trans-septal punch comprising the outer tube and theintermediate tube arranged concentrically and orientedcircumferentially, according to an embodiment of the invention;

FIG. 10 illustrates an oblique view of the proximal end of thearticulating trans-septal punch, according to an embodiment of theinvention;

FIG. 11 illustrates a side view of the distal end of the articulatingtrans-septal punch incorporating a control rod and a control rodretainer, separated from each other, and the outer T-slotted tube withthe inner tube being pulled proximally relative to the outer tubecausing the outer tube to deform into a curve having very stiff, orrigid, mechanical properties, according to an embodiment of theinvention;

FIG. 12A illustrates a top view of a portion of the distal flexibleregion of an outer tube comprising dovetails or interlocking grooves toreduce torque or side-to-side motion, according to an embodiment of theinvention;

FIG. 12B illustrates a side view of a portion of the outer tube distalflexible region of an outer tube comprising dovetails or locking groovesto reduce torque or side-to-side motion, according to an embodiment ofthe invention;

FIG. 13 illustrates the distal end of an articulating septal punchadvanced nearly to the distal end of an obturator or dilator, which iscoaxially, removably assembled into the central lumen of a guidecatheter sheath, according to an embodiment of the invention;

FIG. 14 illustrates the distal end of an articulating transseptal punchfurther comprising a removable obturator having a collapsible distalshield, according to an embodiment of the invention;

FIG. 15A illustrates an outer tube cut in its flexible regions withshorter lateral slots and with reduced or complete elimination of someT-slots to improve resistance to bending in that region, according to anembodiment of the invention;

FIG. 15B illustrates a control rod without any control rod retainerleaving only the c-shaped control rod and the distal end, according toan embodiment of the invention;

FIG. 16A illustrates a cross-sectional view of a control rodconfiguration in a steerable transseptal punch within the flexibleregion, wherein the separation between the control rod and a control rodretainer is substantially at the midpoint or center of the outer tubing,according to an embodiment of the invention;

FIG. 16B illustrates a lateral cross-section of a tubing configurationof a steerable transseptal punch within the flexible distal region, withan off-center slot, according to an embodiment of the invention;

FIG. 17A illustrates a cross-sectional view of a steerable transseptalpunch comprising an outer tube and three control rods, each subtendingapproximately ⅓ of the internal circumference of the outer tube, some orall of which can be functional and each of which is separated from theother by the spacing and all residing within the central lumen of theouter tube, according to an embodiment of the invention;

FIG. 17B illustrates a cross-sectional view of a steerable transseptalpunch comprising an outer tube and four control rods, each subtendingapproximately ¼ of the internal circumference of the outer tube, some orall of which can be functional and each of which is separated from theother by the spacing and all residing within the central lumen of theouter tube, and further including an innermost tube to control the fluidpath and prevent ingress of egress of fluid from the central lumen ofthe punch assembly, according to an embodiment of the invention;

FIG. 18A illustrates a lateral cross-section of a steerable transseptalpunch comprising an outer tube, a control rod, a control rod retainer,an internal pressure sleeve to prevent ingress or egress of fluids, anda stylet, according to an embodiment of the invention;

FIG. 18B illustrates a lateral cross-section of a steerable transseptalpunch comprising an outer tube, two control rods subtending (together) ½of the internal circumference of the inner lumen and a control rodretainer subtending ½ of the internal circumference of the outer tube,along with a central stylet, according to an embodiment of theinvention;

FIG. 18C illustrates a side view of a control rod and keeper systemcomprising a c-shaped control rod and a c-shaped control rod guide,retainer, or keeper configured to maintain the control rod against theinside diameter of an outer tube and further comprising ends configuredfor welding and providing a fluid-tight seal with other structureswithin a punch, according to an embodiment of the invention.

FIG. 19A illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube and a control rod in the shape of a “V”or “L”, according to an embodiment of the invention;

FIG. 19B illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube and a control rod in the shape of a openended box or “U”, according to an embodiment of the invention;

FIG. 20A illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube and two hollow control rods, each ofwhich having a circular cross-section, according to an embodiment of theinvention;

FIG. 20B illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube, two hollow control rods, and a stylet,each of which comprising a circular cross-section, according to anembodiment of the invention;

FIG. 21A illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube, a rectangular control rod with roundedends and a round stylet within a lumen of the control rod, according toan embodiment of the invention;

FIG. 21B illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube and an I-beam shaped control rod,according to an embodiment of the invention;

FIG. 22A illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube having a central lumen and a control roddisposed within the central lumen, according to an embodiment of theinvention;

FIG. 22B illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube, a hollow control rod disposed within thelumen of the outer tube, and a stylet disposed within the lumen of thecontrol rod, according to an embodiment of the invention;

FIG. 23A illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube having a central lumen and a control roddisposed within the central lumen, the control rod having a centrallumen and two channels to retain the one or more control wires or rods,according to an embodiment of the invention;

FIG. 23B illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube, a control rod, and a control rod guide,the guide and the control rod being separated by slots formed at anangle other than radial, according to an embodiment of the invention;

FIG. 24A illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube having a central lumen, a control roddisposed within the central lumen of the outer tube, the control rodhaving a central lumen and subtending less than a full circlecircumferentially, and a central stylet, according to an embodiment ofthe invention;

FIG. 24B illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube, a c-shaped control rod, and a controlrod guide having thinner wall than the control rod, the guide and thecontrol rod being separated by slots formed radially, according to anembodiment of the invention;

FIG. 25A illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube having a central lumen, a c-shapedcontrol rod disposed within the central lumen of the outer tube, ac-shaped control rod retainer, and narrow slots separating the controlrod and the retainer, according to an embodiment of the invention;

FIG. 25B illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube having a central lumen, a c-shapedcontrol rod disposed within the central lumen of the outer tube, ac-shaped control rod retainer, and medium width slots separating thecontrol rod and the retainer, according to an embodiment of theinvention;

FIG. 25C illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube having a central lumen, a c-shapedcontrol rod disposed within the central lumen of the outer tube, ac-shaped control rod retainer, extremely wide slots separating thecontrol rod and the retainer, and a large gap between the OD of thecontrol rod and retainer and the ID of the outer tube, according to anembodiment of the invention;

FIG. 26A illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube having a central lumen, a plurality ofcontrol rods or wires, an intermediate tube, and a central stylet,according to an embodiment of the invention;

FIG. 26B illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube having a central lumen, a plurality ofhollow tubular control rods or wires, an intermediate tube, and acentral stylet, according to an embodiment of the invention;

FIG. 27A illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube having a central lumen and a solidcentral control rod slidably disposed therein, according to anembodiment of the invention;

FIG. 27B illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube having a central lumen, a semi-circularfirst solid control rod, and a semi-circular solid control rod retaineror second control rod, according to an embodiment of the invention;

FIG. 28A illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube having a central lumen and a plurality ofradially oriented cuts or grooves disposed in two generally orthogonaldirections, the different cuts or grooves being interdigitated betweeneach other along the length of a flexible region, a plurality of controlrods and a control rod retainer, according to an embodiment of theinvention;

FIG. 28B illustrates a lateral cross section of the steerabletransseptal punch comprising an outer tube having a central lumen, twoquarter-circular arcuate control rods, and a semi-circular hollowcontrol rod retainer, according to an embodiment of the invention;

FIG. 29A illustrates a lateral cross section of a steerable transseptalpunch comprising an outer tube having a central lumen and a plurality ofradially oriented cuts or grooves disposed in two generally orthogonaldirections, the different cuts or grooves being placed in order with thegrooves in the first direction in a different axial region of the tubethan the grooves in the second direction and each defining a flexibleregion in a specific direction, a plurality of control rods, a pluralityof distal weld points, and a control rod retainer, according to anembodiment of the invention;

FIG. 29B illustrates a lateral cross section of the steerabletransseptal punch comprising an outer tube having a central lumen, twoquarter-circular arcuate control rods, and a semi-circular hollowcontrol rod retainer, according to an embodiment of the invention;

FIG. 30A illustrates a lateral cross section of a steerable transseptalneedle comprising an outer tube having a central lumen and a pluralityof radially oriented openings, cuts, or grooves disposed in a singledirection, defining a flexible region in a specific direction, a hollowcircular control rod, a distal weld point between the control rod andthe outer tube, a pressure jacket over the openings in the outer tube toprevent fluid leakage or ingress, and a distal hinge on the control rod,according to an embodiment of the invention;

FIG. 30B illustrates a lateral cross section of the steerabletransseptal punch comprising an outer tube having a central lumen and ahollow circular, tubular control rod having a central lumen, accordingto an embodiment of the invention;

FIG. 31A illustrates a side view of a steerable transseptal needlecomprising a blunt distal end and a sharp, tissue piercing stylet orobturator, in its retracted state, according to an embodiment of theinvention;

FIG. 31B illustrates a side view of the steerable transseptal needle ofFIG. 31A with the sharp stylet or obturator advanced distally beyond thedistal end of the inner tube to form a sharp, tissue punch, according toan embodiment of the invention;

FIG. 32A illustrates a steerable transseptal needle comprising aradiopaque marker at the distal end of the inner tube as well as a smalldiameter segment of the stylet wire, according to an embodiment of theinvention;

FIG. 32B illustrates the steerable transseptal needle of FIG. 32A withthe stylet advanced out the distal end of the inner tube, according toan embodiment of the invention;

FIG. 33A illustrates a steerable transseptal needle comprising a beveledtip, sharp stylet, according to an embodiment of the invention;

FIG. 33B illustrates the steerable transseptal needle of FIG. 33A withthe beveled sharp stylet advanced out the distal end of the inner tube;

FIG. 34A illustrates a hub configured for use with a piercing stylet orobturator in its retracted state, according to an embodiment of theinvention;

FIG. 34B illustrates the hub of FIG. 34A actuated such that the styletor obturator is advanced a controlled distance, according to anembodiment of the invention;

FIG. 35A illustrates a side exterior view of a stylet hub furthercomprising a removable safety clip, according to an embodiment of theinvention;

FIG. 35B illustrates the hub of FIG. 35A in oblique view, according toan embodiment of the invention;

FIGS. 36A, 36B and 36C illustrate side views of a steerable transseptalneedle with a piercing stylet hub removably affixed to the proximal endof the needle hub, according to an embodiment of the invention;

FIG. 37 illustrates a top view of a steerable transseptal needlecomprising a three-way stopcock affixed to its hub, rather than thestandard one-way stopcock, according to an embodiment of the invention;

FIG. 38 illustrates a faceted sharp distal end of a piercing stylet,according to an embodiment of the invention;

FIG. 39A illustrates a side, partial breakaway view of the distal end ofa steerable transseptal needle wherein a portion of the stylet shaft hasbeen cut away to facilitate fluid flow within the central lumen of thesteerable transseptal needle, according to an embodiment of theinvention;

FIG. 39B illustrates a lateral cross-section of a stylet wire configuredto facilitate fluid flow or pressure measurement while the stylet wireis in place within the steerable transseptal needle lumen, according toan embodiment of the invention; and

FIG. 40 illustrates a hub of a steerable transseptal needle safetypiercing stylet wherein the hub comprises magnetic latches to actuatethe stylet, according to an embodiment of the invention.

DETAILED DESCRIPTION

In accordance with current terminology pertaining to medical devices,the proximal direction will be that direction on the device that isfurthest from the patient and closest to the user, while the distaldirection is that direction closest to the patient and furthest from theuser. These directions are applied along the longitudinal axis of thedevice, which is generally an axially elongate structure having one ormore lumens or channels extending through the proximal end to the distalend and running substantially the entire length of the device.

In an embodiment, the invention is an endoluminally, transvascularly, orendovascularly placed tissue punch, with internal deflectability or theability to articulate, at its distal end, in a direction away from itslongitudinal axis. The punch can also be termed a catheter, needle, orcannula. The punch is generally fabricated from stainless steel andcomprises an outer tube, an intermediate tube, a central stylet wire,and a distal articulating region. The deflecting or articulatingmechanism is integral to the punch. The punch, needle, or catheter issufficiently rigid, in an embodiment, that it can be used as an internalguidewire or internal guide catheter. The punch is useful for animals,including mammals and human patients and is routed through body lumensor other body structures to reach its target destination.

In an embodiment, the punch comprises an inner core wire or stylet, anintermediate tube and an outer tube. In an embodiment, the stylet can beremovable or non-removable. The punch further comprises a hub at itsproximal end which permits grasping of the punch and also includes astopcock or valve to serve as a lock for the stylet, or inner core wire,as well as a valve for control of fluid passage into and out from theinnermost lumen within which the stylet or inner core wire resides. Theproximal end further comprises one or more control handles to manipulatethe amount of articulation at the distal end of the catheter. Theproximal end further is terminated with a female Luer or Luer lock port,which is suitable for attachment of pressure monitoring lines, dyeinjection lines, vacuum lines, a combination thereof, or the like.

The punch is fabricated so that it is substantially straight from itsproximal end to its distal end. Manipulation of a control mechanism atthe proximal end of the punch causes a distal region of the punch tobend or curve away from its longitudinal axis. The bending, steering, orarticulating region is located near the distal end of the punch and canbe a flexible region or structure placed under tension or compression bypull wires or control rods routed from the control handle at theproximal end of the punch to a point distal to the flexible region. Theflexible region is thus a region at the distal end of the outer tubethat is significantly more flexible and susceptible to deflection thanthe remaining proximal region of the outer tube. In another embodiment,the bending or articulating mechanism can also be created by pre-bendingthe outer tube in one direction and bending the intermediate tube inanother direction. The two tubes can be rotated relative to each other,about their longitudinal axis, by turning knobs or grips at the proximalend of the punch. When the curvatures of both tubes are aligned, thetubes will generally cooperate and not oppose each other, thus, maximumcurvature or deflection is generated. When the tubes are rotated sotheir natural curvatures are aligned 180 degrees from each other, thecurves will oppose each other or cancel out. Thus, the nested tubes willbe substantially straight when the curvatures of the two concentrictubes oppose each other. Alignment marks or graduations at the proximalend can be used to assist with proper rotational alignment of the twotubes. The central core wire or stylet is generally straight andflexible and does not contribute to the curvature. In anotherembodiment, however, the stylet can be imparted with a curvature toassist with steering or articulation. Rotation of the two concentrictubes at relative angles between about 180 degrees and 0 degrees willresult in intermediate amounts of deflection so the amount of deflectioncan be increased or decreased in an analog, continuously variable,digital, or stepwise fashion. The stepwise or digital response can begenerated using detents or interlocks that weakly engage at specificpre-determined locations. A locking mechanism can be further utilized tohold the two tubes in rotational alignment once the desired amount ofcurvature has been achieved.

In another embodiment, steerability can be obtained using actuators onthe surface or within the interior of the cannula to force bending ofthe cannula. These actuators can be typically electrically powered. Inan embodiment, an actuator can comprise electrical leads, a powersource, a compressible substrate, and shape memory materials such asnitinol. Such actuators may be distributed along the length of thecannula. The actuators may be placed so as to oppose each other.Opposing actuators are activated one at a time and not simultaneouslyand can generate a steering effect or back and forth motion.

Other embodiments of the inventions comprise methods of use. One methodof use involves inserting the central core wire or stylet so that itprotrudes out the distal end of the punch. A percutaneous or cutdownprocedure is performed to gain access to the vasculature, either a veinor an artery. An introducer and guidewire are placed within thevasculature and the guidewire is routed proximate to the targettreatment site. The introducer can be removed at this time. A guidingcatheter, preferably with a removable central obturator or dilator, witha tapered distal tip pre-inserted, is routed over the guidewire to thetarget site. In some embodiments, the guide catheter is routed throughfrom a femoral vein, through the inferior vena cava, and into the rightatrium of the heart. In an embodiment, the target site can be the atrialseptum of the heart in the region of the Fossa Ovalis. In someembodiments, the guide catheter distal tip is routed past the rightatrium and into the superior vena cava. The guidewire can be removed atthis time. The punch is adjusted so that it assumes a substantiallystraight configuration. The punch can be advanced through the centrallumen of the already placed catheter, sheath, introducer, or guidecatheter. By making the punch as straight as possible, there is nocurvature to force the sharpened distal edges of the punch to scrape theinside of the catheter lumen as the punch is advanced distally insidethe guide catheter and potentially dislodge or skive away debris ormaterial which could cause embolic effects to the patient. Carefullyensuring that the punch does not protrude beyond the distal end of thecatheter or its obturator, the punch is next deflected so that it formsa curve. The distal end of the punch is sufficiently radiopaque that itis observable clearly under fluoroscopy or X-ray imaging. The locationof the punch and the amount of deflection and curvature of the distalend are observed and controlled using the aforementioned fluoroscopy orX-ray imaging, or other imaging method such as MRI. The curve isoriented so that it is medially directed toward the atrial septum.Alignment with any curvature of the catheter can be completed at thistime. The punch and guide catheter/obturator are withdrawn caudally, asa unit, into the right atrium from the superior vena cava. The punch andguide catheter are positioned using fluoroscopy or other imaging systemagainst the Fossa Ovalis. The Fossa Ovalis is a relatively thinstructure and the force of the punch will tent the Fossa Ovalis towardthe left atrium. In one embodiment, the central core wire or stylet,initially advanced, can next be withdrawn to expose the sharp distaledge of the punch. When correctly positioned under fluoroscopy,ultrasound, or other imaging system, dye can be injected into thecentral lumen of the punch at its proximal end and be expelled out ofthe distal end of the punch and obturator to paint or mark the FossaOvalis. A generally “V-shaped” mark can be observed under fluoroscopy,which denotes the location of the Fossa Ovalis. The curvature of thepunch can be increased or decreased by articulation to gain optimalalignment with the Fossa Ovalis. This steering function can be verybeneficial in device placement.

Maintaining the position of the guiding catheter against the FossaOvalis, the punch is advanced distally against and through the atrialseptum, in the region of the Fossa Ovalis, so that it penetrates andprotrudes into the left atrium. In order to stabilize the atrial septaltissue prior to coring, a distally protruding corkscrew tipped wire or avacuum head operably connected to the proximal end of the punch, can beused to grasp and retract the septal tissue. Once the initialpenetration is completed, the guide catheter is next advanced, with itstapered obturator leading the way, across the atrial septum until itresides within the left atrium. The tapered obturator or dilator alongwith the punch can be removed at this time to allow for catheterplacement through the guiding catheter. In another embodiment, acalibrated spacer can be used between the guide catheter hub and thepunch hub to ensure that the punch does not protrude beyond the distalend of the guide catheter tip until the desired time for punching thehole. At this point, the spacer is unlocked and removed from the punchor catheter. In some embodiments, the punch is removed from the guidecatheter and the same punch is routed through a second guide catheter toprovide access to the left atrium for the second guide catheter. Twoguide catheters are often necessary for ablation procedures because oneguide catheter is used to route mapping and diagnostic devices into theleft atrium while the second guide catheter is used to route therapeuticcatheters into the left atrium. Thus, the punch can be used more thanonce on a given patient but, for prevention of contamination, the samepunch should not be used on different patients because cleaning andsterilization after use is nearly impossible given the small distancesbetween the moving inner and outer tubes which can hide contaminationfrom cleaning or sterilization by the user.

In another embodiment, the core wire, obturator or stylet is sharpenedand serves as a tissue punch. In this embodiment, the distal end of thehollow tubes of the punch are blunted and made relatively atraumatic.Once the core wire punch has completed tissue penetration, the outertubes are advanced over the central punch wire through the penetrationand into the left atrium. In another embodiment, a pressure monitoringdevice such as a catheter tip pressure transducer, or a pressure lineterminated by a pressure transducer, can be affixed to a quick connect,generally a Luer fitting, at the proximal end of the punch hub. Bymonitoring pressure, it is possible to determine when the distal end ofthe punch has passed from, for example, the right atrium into the leftatrium, because the pressure versus time curves in these two chambersare measurably, or visually, different. The proximal end of the hubfurther has provision for attachment to a dye injection line for use ininjecting radiographic contrast media through the central lumen of thepunch. Typically a manifold can be attached to the Luer fitting on theproximal end of the hub, the manifold allowing for pressure monitoring,for example on a straight through port, and for radiopaque dyeinjection, for example through a side port. A stopcock, or other valve,can be used to control which port is operably connected to the centrallumen of the punch.

In some embodiments, the inner tube, the outer tube, or both can haveslots imparted into their walls to impart controlled degrees offlexibility. The slots can be configured as “snake cuts” to form aseries of ribs with one or more spines. The spines can be oriented at agiven circumferential position on the outer tube, the inner tube, orboth. The spines can also have non-constant orientations. In someembodiments, only the outer tube is slotted. The slots can be generatedwithin the distal portion of the outer tube where the curve isgenerated. This distance can range between 3-cm and 15-cm of the end andpreferably between 7-cm and 12-cm of the distal end. The slot widths canrange between 0.001 inches and 0.100 inches with a preferable width of0.003 to 0.025 inches. In exemplary embodiments, the slot widths areabout 0.010 inches. In some embodiments, it is desirable to have theouter tube bend in one direction only but not in the opposite directionand not in either lateral direction. In this embodiment, cuts can bemade on one side of the outer tubing within, for example, the distal10-cm of the tube length. Approximately 10 to 30 cuts can be generatedwith a width of approximately 0.010 to 0.040 inches. The cut depth,across the tube diameter from one side, can range between 0.1 and 0.9 ofthe tube diameter. In an embodiment, the cut depth can be approximately0.4 to 0.6 of the tube diameter with a cut width of 0.025 inches. Asecond cut can be generated on the opposite side of the tube wherein thesecond cut is approximately 0.005 inches or less. In an embodiment, theouter tube can be bent into an arc first and then have the slotsgenerated such that when the tube is bent back toward the 0.005 inchwide cuts, the tube will have an approximately straight configurationeven through each tube segment between the cuts is slightly arced orcurved.

FIG. 1 illustrates a side view of a punch, needle, or catheter assembly100, with an integral articulating or bending mechanism. The punchassembly 100 comprises a stylet or obturator wire 102, an intermediatetube 104, an outer tube 106, an obturator grasping tab 108, a stopcock110, an intermediate tube pointer 112, an outer tube pointer 114, anintermediate tube hub 116, and an outer tube hub 118. The obturator wire102 is affixed to the obturator grasping tab 108. The stylet orobturator wire 102 is inserted through the central lumen of theintermediate tube 104 and is slidably disposed therein. The stopcock 110is affixed to the intermediate tube hub 116 and the through lumen of thestopcock 110 is operably connected to the central lumen of theintermediate tube 104. The intermediate tube pointer 112 is affixed tothe intermediate tube hub so that it is visible to the user. The outertube pointer 114 is affixed to the outer tube hub 118 so that it isvisible to the user. The intermediate tube hub 116 and the intermediatetube 104 are able to rotate about the longitudinal axis within the outertube hub 118 and the outer tube 106. In an embodiment, the intermediatetube 104 is restrained from longitudinal motion relative to the outertube 106. In another embodiment, the intermediate tube 104 can beadvanced distally relative to the outer tube 106. In this latterembodiment, advancement of the inner tube 104 can be used to facilitatepunching. The distal end of the intermediate tube 104 can be sharpenedand serve as a punch. The distal end of the intermediate tube 104 issheathed inside the outer tube 106 to protect the tissue from the sharpdistal edge of the intermediate tube 104 until the intermediate tube 104is advanced distally outside the distal end of the outer tube 106. Areleasable lock can be used to maintain the axial or longitudinalposition of the intermediate tube 104 relative to the outer tube 106until punching is required. A releasable lock can further be used tomaintain the rotational position of the intermediate tube hub 116 andthus the intermediate tube 104 relative to the outer tube hub 118 andthe outer tube 106.

All components of the punch assembly 100 can be fabricated from metalssuch as, but not limited to, stainless steel, Elgiloy™, cobalt nickelalloy, titanium, nitinol, or the like. The nitinol can be shape-memoryor it can be superelastic. The metals used in the obturator wire 102,the intermediate tube 104 and the outer tube 106 are advantageously coldrolled, heat treated, or otherwise processed to provide a full springhardness. The intermediate tube 104, the outer tube 106, or both, arerelatively rigid, resilient structures. Polymeric materials, such as,but not limited to, polycarbonate, ABS, PVC, polysulfone, PET,polyamide, polyimide, and the like, can also be used to fabricate thestopcock 110, the intermediate tube hub 116, the outer tube hub 118, theintermediate tube pointer 112, and the outer tube pointer 114. Thematerials are beneficially radiopaque to maximize visibility underfluoroscopy during the procedure. Additional radiopaque markersfabricated from tantalum, platinum, iridium, barium sulfate, and thelike can be added to improve visibility if needed. The intermediate tube104 is curved or bent near its distal end into a gentle curve,preferably with a radius of between 1 to 5 inches and so that the distaltip is deflected through an angle of approximately 10 to 90 degrees fromthe longitudinal axis of the intermediate tube 104. The outer tube 106is curved or bent near its distal end into a gentle curve, preferablywith a radius of between 1 to 5 inches and so that the distal tip isdeflected through an angle of approximately 10 to 90 degrees from thelongitudinal axis of the outer tube 106. The intermediate tube hub 116is welded, silver soldered, bonded, crimped, or otherwise fastened tothe proximal end of the intermediate tube 104 so that the intermediatetube pointer 112 points in the direction of the bend in the intermediatetube 104. The outer tube hub 118 is welded, silver soldered, bonded,crimped, or otherwise fastened to the proximal end of the outer tube 106so that the outer tube pointer 114 points in the direction of the bendin the outer tube 106. When the intermediate tube pointer 112 isoriented 180 degrees away from the direction of the outer tube pointer114, the bend in the intermediate tube 104 substantially counteracts oropposes the bend of the outer tube 106 and the coaxial assembly 100 issubstantially straight, as shown in FIG. 1 . The stopcock 110 can alsobe a ring seal, Tuohy-Borst valve, membrane valve, hemostasis valve,gate valve, or other valve, generally, but not necessarily manuallyoperated. The stiffness of the intermediate tube 104 and the outer tube106 are sufficient that the punch can be used as a guide for othercatheters through which the punch 100 is passed and will deflect thosecatheters, even ones that have thick walls and high resistance tobending.

FIG. 2 illustrates a side view of a stylet or obturator 140 furthercomprising the obturator wire 102 and the obturator-grasping tab 108.The obturator wire 102 is blunted at its distal end to render it asatraumatic as possible. In another embodiment, the obturator wire 102can be tapered in diameter to render it very flexible and thereforeatraumatic at its distal end. The obturator wire 102, in anotherembodiment, can be sharpened and serve as a needle or primary punchingmechanism. FIG. 2 also illustrates an intermediate punch assembly 120further comprising the intermediate tube 104, the stopcock 110, theintermediate tube pointer 112, the intermediate tube hub 116, anintermediate tube seal 124, an intermediate tube pointer ball 126, athrough lumen port 128, a beveled distal tip 132, and a pre-set curve136. FIG. 2 further illustrates an outer tube assembly 122 furthercomprising the outer tube 106, the outer tube hub 118, the outer tubepointer 114, an outer tube distal curve 130, and an outer tube pointerball 134.

Referring to FIG. 2 , the obturator-grasping tab 108 is affixed, eitherintegral to, silver soldered, welded, crimped, adhered, pinned, orotherwise attached, to the proximal end of the obturator wire 102. Theintermediate tube 104 is affixed to the intermediate tube hub 116 bysilver soldering, welding, potting, crimping, setscrew, pin, or otherfixation method, such that the hub 116 rotates 1 to 1 with theintermediate tube 104. An optional intermediate tube pointer ball 126 isaffixed to the intermediate tube pointer 112 and provides additionalvisual and tactile rotational positioning sense for the intermediatepunch or needle assembly 120. A curve or bend 136 is heat set, or coldworked into the intermediate tube 104 at or near its distal end. Thedistal end of the intermediate tube 104 comprises a bevel 132 whichhelps serve as a punch or cutting edge for the intermediate tube 104.The angle of the bevel 132 can range between 20 and 70 degrees from thedirection perpendicular to the longitudinal axis of the intermediatetube 104. In another embodiment, the bevel is removed and the distal tipof the intermediate tube 104 is a gentle inward taper or fairing movingdistally that serves as a dilator should the obturator wire 102 be usedas the punching device rather than the blunt distal tip obturator of theintermediate tube 104. The intermediate tube hub 116 further comprises acircumferential groove with an “0” ring 124 affixed thereto. The “0”ring 124 serves to form a fluid (e.g. air, blood, water) tight seal withthe inner diameter of the outer sheath hub 118 central lumen and allowsfor circumferential rotation of the intermediate tube hub 116 within theouter tube hub 118. The “0” ring 124 can be fabricated from rubber,silicone elastomer, thermoplastic elastomer, polyurethane, or the likeand may be lubricated with silicone oil or similar materials. Thestopcock 110 can be a single way or a three-way stopcock without or witha sideport, respectively.

The outer punch assembly 122 comprises the bend 130, which is heat setor cold worked into the outer tube 106 in the same longitudinal locationas the bend 136 of the intermediate tube. The wall thicknesses of theintermediate tubing 104 and the outer tubing 106 are chosen to providebending forces that cancel out when the curves 136 and 130 are orientedin opposite directions and the intermediate tubing 104 is inserted fullyinto the outer tubing 106. The wall thickness of the outer tube 106 andthe intermediate tube 104 can range between 0.003 inches and 0.20inches, preferably ranging between 0.004 and 0.010 inches. The outerdiameter of the outer tube 106 can range between 0.014 and 0.060 inchesand preferably between 0.025 and 0.050 inches. In a most preferredembodiment, the outside diameter of the outer tube 106 is about 0.048inches. The outer diameter of the obturator wire 102 can range between0.005 and inches and preferably range between 0.010 and 0.020 inches.

FIG. 3 illustrates a side view of the punch assembly 100 fully assembledand aligned so that both the intermediate tube distal curve 136 (Referto FIG. 2 ) and the outer tube distal curve 130 are aligned in the samedirection resulting in a natural bend out of the axis of the punch 100.The punch assembly 100 comprises the obturator wire 102, theintermediate tube 104, the outer tube 106, the obturator grasping tab108, the stopcock 110, the intermediate tube pointer 112, the outer tubepointer 114, the intermediate tube hub 116, the intermediate tubepointer ball 126, and the outer tube pointer ball 134. The outer tubepointer 114 and intermediate tube pointer 112 are aligned together andin this configuration, the tubing assembly possesses its maximumcurvature, which is oriented in the same directions as the pointers 112and 114. The pointer balls 126 and 134 are aligned together to provideadditional tactile and visual indices of curvature direction. In anembodiment, the curvature of the tube assembly 104 and 106 is unbiasedwith no net force exerted therebetween and an angle of approximately 45degrees is subtended by the device in the illustrated configuration.Further curvature can also occur out of the plane of the page so thatthe curvature takes on a 3-dimensional shape, somewhat similar to acorkscrew. In another embodiment, the curvature of the aligned innertube 104 and the outer tube 106 subtends an angle of 90-degrees orgreater. Again, the intermediate tube 104 and the outer tube 106 havestiffness sufficient that the assembly is capable of guiding anycatheter through which the punch 100 is passed. In another embodiment,the intermediate tube 104 and the outer tube 106 have different degreesof curvature so that when they are aligned, a net force still isgenerated between the two tubes, although a maximum curvatureconfiguration is still generated. This embodiment can be advantageous inpermitting articulation in a direction away from the direction ofprimary curvature. The radius of curvature of the punch 100 can rangefrom substantially infinity, when straight, to as little as 0.5-cm, witha preferred range of infinity to as little as 2-cm radius when fullycurved or articulated. One embodiment permits a substantially infiniteto a 3-cm radius of curvature. The overall working length of the punch,that length from the proximal end of the outer tube hub to the distalmost end of the punch, can range from 10 to 150-cm and preferablybetween 60 and 100-cm, with a most preferred range of between 70 and90-cm. A preferred curve has a radius of about 3-cm and is bent into anarc of about 45 to 90 degrees.

FIG. 4 illustrates a side view of another embodiment of a needle orpunch assembly 400 comprising an obturator wire 102, an obturator wiregrasping tab 108, a stopcock 110, an intermediate tube 404, an outertube 406, a plurality of deflecting wires 412, an outer tube hub 414, adeflecting lever 416, a weld 420, an axis cylinder 424, a plurality ofdeflecting wire channels 426, and a flexible region 430. The distal endof the region just proximal to the flexible region 430 is shown inbreakaway view. Furthermore, the distal end of the region just proximalto the flexible region 430 as well as the flexible region 430 has beenexpanded in scale so that certain details are more clearly visible. Theflexible region 430 is affixed to the outer tube 406 by a weld 420. Theflexible region 430 can also be fixed to the outer tube 406 by a crimp,pin, setscrew, adhesive bond, interference fit, mechanical interlock,thread, or the like. The attachment between the flexible region 430 andthe outer tube 406 is made at the proximal end of the flexible region430 and a second attachment or weld 420 can be made at the distal end ofthe flexible region 430 so as to attach to a length of distal outer tube406. The flexible region 430 can comprise a length of coiled wire suchas that used in guidewires, it can be a tube that comprises cutouts toprovide a backbone configuration to impart flexibility, it can be alength of polymeric tube with elastomeric characteristics, or it can beanother type of structure that is known in the art as providingflexibility. These preferred structures also advantageously providecolumn strength and kink resistance to the flexible region 430. Thecenter of the flexible region 430 is hollow and comprises a lumen, whichis operably connected to the central lumen of the outer tube 406 at boththe proximal and distal end of the flexible region 430. The stopcock 110is affixed, at its distal end, to the outer tube hub 414. The outer tubehub 414 further comprises a deflecting lever 416 that is affixed to theaxis cylinder 424, which serves as an axle or rotational pin, and can bemoved proximally or distally by manual action on the part of theoperator or by a motor or other electromechanical actuator (not shown).The deflecting lever 416 is operably connected to the proximal ends ofthe deflecting wires 412. In an exemplary embodiment, one of thedeflecting wires 412 is affixed to the top of the axis cylinder 424 andthe other deflecting wire is affixed to the bottom of the axis cylinder424. When the deflecting lever is pulled proximally, for example, thetop wire 412 is placed under tension and the tension on the bottom wireis relieved causing tension to be exerted on the distal end of the punch400. The deflecting wires 412 are slidably routed through the deflectingwire channels 420 within the outer tube 406. The deflecting wires 412also run through the deflecting wire channels 420 within the flexibleregion 430. The deflecting wires 412 can also be routed through theinternal lumen of the outer tube 406 and the flexible region 430.

Referring to FIG. 4 , the outer tube hub 414 is affixed to the proximalend of the outer tube 406 by a crimp, pin, setscrew, adhesive bond,interference fit, mechanical interlock, thread, or the like. Theintermediate tube 404 is affixed to the distal end of the outer tube 406by a crimp, pin, setscrew, adhesive bond, interference fit, mechanicalinterlock, thread, or the like. In another embodiment, the intermediatetube 404 is routed throughout the length of the outer tube 406. In thisembodiment, the intermediate tube can comprise grooves (not shown) thatserve as deflecting wire channels 420 when the intermediate tube 404 isinserted inside the outer tube 406. Such grooves can also be disposed onthe interior surface of the outer tube 406, rather than on the exteriorsurface of the inner tube 404. The obturator wire 102 and the attachedgrasping loop 108 are slidably disposed within the inner lumen of theouter tube 406, or the intermediate tube 404. The intermediate tube 404is gently tapered up to the outer tube 406 at the distal end of theouter tube 406 in a transition region so that a dilator effect can becreated during distal advancement of the punch 400. The distal end ofthe intermediate tube 404 can comprise a bevel 132 (FIG. 2 ) or othersharp point for punching through biological tissue. The distal end ofthe intermediate tube 404 preferably forms a non-coring needle or punchthat does not excise a tissue sample. The non-coring punch feature isachieved by keeping the central lumen closed or very small. Thenon-coring punch 400 embodiment can comprise filling the lumen of theintermediate tube 404 with the obturator or stylet wire 102 to preventthe sharp edge of the intermediate tube from functioning as a trephine.

FIG. 5 illustrates a side view of the punch assembly 400 wherein thedeflecting lever 416 has been withdrawn proximally causing increasedtension in one of the deflecting wires 412, causing the flexible region430 to bend 422 out of the longitudinal axis. The punch assembly 400further comprises the obturator wire 102, the obturator wire graspingtab 108, the stopcock 110, the deflecting lever 416, an axis cylinder424, the hub 414, the outer tubing 406, the intermediate tubing 404, andthe bend 422. The deflecting lever 416 has been moved proximally and theaxis cylinder 424 causing the top deflecting wire 412 to be placed intension while the bottom deflecting wire 412 is relaxed. The deflectingwires 412 are affixed at their distal end to the outer tubing 406 or theintermediate tubing 404 at a point substantially at or beyond the distalend of the flexible region 420. The distal fixation point (not shown) ofthe deflecting wires 412 is off-center from the axis of the outer tubing406 or intermediate tubing 404. When uneven tension is created in theopposing deflecting wires 412, the uneven tension on the distal end ofthe punch 400 causes the flexible region 430 to undergo deflection intoa curve or bend 422. Similarly, forward movement of the deflecting lever416 will place the bottom deflecting wire 412 in tension while the upperdeflecting wire 412 will be relaxed, causing the punch 400 to undergo abend in the opposite direction (downward). The deflecting lever 416 canfurther comprise a ratchet and lock, a friction lock, a spring-loadedreturn, or other features to hold position or cause the lever and theflexible region 430 to return to a neutral deflection configuration(substantially straight). The spring nature of the outer tube 406 andthe flexible region 430 can advantageously be used to cause a return toneutral once the deflection force is removed from the deflecting lever416. The stylet or obturator wire 102 can be withdrawn or extended toexpose or protect (respectively) the distal end of the intermediate tube404 which can be sharpened or blunted. The obturator wire 102 canfurther be used as the primary punch, especially if the distal tip ofthe obturator wire 102 is sharpened. If the obturator wire 102 is usedas the primary punch, the proximal end of the intermediate tube hub isfitted with a Tuohy-Borst or other hemostatic valve to permit theobturator wire 102 to remain in place. In this embodiment, sidearmsaffixed proximal to the proximal end of the punch, and operablyconnected to the central lumen, serve to permit pressure monitoring anddye contrast injection without compromising hemostasis or air entry intothe punch assembly 400.

FIG. 6 illustrates a side view of an adjustable spacer 600interconnecting a guide catheter 620 and a punch assembly 100. Thespacer 600 further comprises a proximal connector 602, a rotating nut604, an inner telescoping tube 608, a threaded region 606, a distallocking connector 610, and an outer telescoping tube 614. The guidecatheter further comprises a tube 622, a hub 624, and a proximalconnector 626. The punch assembly 100 further comprises the stopcock110, the distal rotating locking connector 612, the intermediate tubepointer 112, the outer tube pointer 114, and the intermediate tube hub116. The spacer 600 can comprise an optional slot 630. The punchassembly 100 is inserted through the central lumen of the adjustablespacer 600. The distal end of the punch assembly 100 is then insertedthrough the central lumen of the guide catheter 620. The hub 624 of theguide catheter 620 is affixed to the proximal end of the guide cathetertube 622. The distal end of the hub 624 comprises a female luer lockconnection, which is bonded to, or integrally affixed to the hub 624.The hub 624 can further comprise a seal or hemostasis valve such as aTuohy-Borst fitting. The punch 100 hub 116 is terminated at its distalend by a swivel male luer lock connector 612. The adjustable spacer 600comprises an outer telescoping tube 614, shown in partial cutaway viewthat is terminated at its proximal end with a female luer lock 602. Theproximal end of the outer telescoping tube 614 has a flange that permitsrotational attachment of the rotating nut 604, shown in partial cutawayview, so that the rotating nut is constrained in position,longitudinally, relative to the outer telescoping tube 614 but is freeto rotate. The inner telescoping tube 608 is affixed at its distal endwith a swivel male luer connector 610, or equivalent. The proximal endof the inner telescoping tube 608 is affixed to, or comprises, theintegral threaded region 606. The threaded region 606 mates with theinternal threads on the rotating nut 604. As the rotating nut 604 isrotated, either manually or by an electromechanical device, it movesforward or backward on the inner telescoping tube 608 and threadedregion 606 thus changing the space between the hub 116 of the punch 100and the proximal end of the hub 624 of the guide catheter 620. Thesystem is preferably set for spacing that pre-sets the amount of needleor stylet travel. In an embodiment, the rotating nut 604 comprises aquick release that allows disengagement of the inner telescoping tube608 from the outer telescoping tube 614 so that collapse is permittedfacilitating the tissue punching procedure of advancing the punch 100distally relative to the hub 624. The system further compriseshemostatic valves at some, or all, external connections to prevent airleaks into the punch 100. The telescoping tube 608 can be set todisengage from the outer telescoping tube 614 to allow for longitudinalcollapse so that the punch 100 can be advanced distally to provide itstissue punching function. In another embodiment, the spacer 600comprises the slot 630 that permits the spacer to be removed sidewaysoff the punch 100. The slot 630 is wide enough to allow the outer tube106 to fit through the slot 630 so the spacer 600 can be pulled off, orremoved from, the punch 100 prior to the punching operation. Thus, theslot 630 can be about 0.048 to 0.060 inches wide and extend the fulllength of the spacer 600. With the slot 630, the spacer 600 comprises agenerally “C-shaped” lateral cross-section. The spacer 600 can furthercomprise a slot closure device (not shown) to prevent inadvertentremoval of the punch 100.

In another embodiment, the threaded region 606 and the rotating nut 604are replaced by a friction lock on telescoping tubes, a ratchet lock, orother suitable distance locking mechanism. In yet another embodiment, ascale or series of markings (not shown) is incorporated into theadjustable spacer 600 to display the exact distance between the proximalend and the distal end of the spacer 600. In another embodiment, theproximal end and the distal end of the spacer 600 do not comprise one orboth of the female luer lock 602 or the rotating male luer lock 610. Inthis embodiment, the spacer 600 provides positional spacing but does notaffix the punch 100 to the guide catheter 620 so that the two devicesmove longitudinally as a unit. In another embodiment, the pull wires 412of FIG. 4 , which are strong in tension but cannot support compressionare replaced by one or more control rods, which are flexible but whichhave column strength. Thus, deflection can be generated by impartingeither tension on the control rod or compression and such tension andcompression is capable of deflecting the distal tip of the punch 400without the need of a separate control rod to impart tension in theother direction. The intermediate tube hub 116 is terminated at itsproximal end by a female luer, luer lock, threaded adapter, bayonetmount, or other quick release connector. The quick connect or femaleluer can be releasably affixed to a hemostasis valve, other stopcock,pressure transducer system, “Y” or “T” connector for pressure andradiopaque contrast media infusion, or the like.

In another embodiment, a vacuum line can be connected to a port affixedto the proximal end of the punch. The port can be operably connected toa bell, cone, or other structure at the distal end of the punch by wayof a lumen, such as the central lumen of the intermediate tube or anannulus between the intermediate and outer tube, within the punch. Byapplication of a vacuum at the proximal end of the punch, the distalstructure can be releasably secured to the atrial septum prior topunching through. In another embodiment, a corkscrew structure projectsout the distal end of the punch and is operably connected to a knob orcontrol at the proximal end of the punch by way of a control rodslideably or rotationally free to move within a lumen of the punch. Thecorkscrew structure can be screwed into tissue to releasably secure thedistal end of the punch to the tissue, for example, to enhance stabilityof the punch prior to, during, or after the punching operation.

Referring to FIG. 1 , in another embodiment, the intermediate tube 104,the outer tube 106, or both, are fabricated from shape memory nitinol.In this embodiment, electrical energy can be applied to the pre-bentregions of the inner tube 104, the outer tube 106, or both. Uponapplication of electrical energy, Ohmic or resistive heating occurscausing temperature of the tubes to increase. The nitinol changes itsstate from martensitic to austenitic, with the increase in temperature,and can assume a pre-determined configuration or stress state, which isin this case curved. The austenite finish temperature for such aconfiguration is approximately 40 degrees centigrade or just above bodytemperature. In yet another embodiment, the austenitic finishtemperature can be adjusted to be approximately 28 to 32 degreescentigrade. The punch 100 can be maintained at room temperature where itis substantially martensitic and non-rigid. Upon exposure to bodytemperatures when it is inserted into the core lumen of the guidecatheter, it will assume its austenitic shape since body temperature isaround 37 degrees centigrade. This can cause the punch 100 to curve fromsubstantially straight to substantially curved. In this configuration,only a single tube, either the intermediate tube 104 or the outer tube106 is necessary, but both tubes, while potentially beneficial, are notrequired.

FIG. 7A illustrates a side view, in partial breakaway, of the distal endof an axially elongate outer tube 710, comprising a lumen 714, aproximal, uncut portion 712, a plurality of lateral partial cuts 716,and a plurality of longitudinal “T” cuts 718, according to anembodiment. The outer tube 710 serves as the outer tube of anarticulating septal punch such as that illustrated in FIG. 5 . Theplurality of partial lateral cuts 716 serve to render the region of theouter tube 710 in which the lateral cuts 716 are located more flexiblethan the proximal region 712. The plurality of longitudinal “T” cuts,serve to further render the region of the outer tube 710, in which the“T” cuts 718 reside, more flexible than in tubes where such “T” cuts 718were not present. The longitudinal “T” cuts 718 are optional but arebeneficial in increasing the flexibility of the outer tube 710 in theselected bend region. The partial lateral slots 716 can be spaced apartby about 0.02 to about 1.0 inches with a preferred range of about 0.1inches to about 0.8 inches and a further preferred range of about 0.15inches to about 0.5 inches. In an exemplary embodiment, the partiallateral slots 716 are spaced about 0.17 inches apart. The spacingbetween the partial lateral slots 716 can vary. In some embodiments, forexample, the spacing between the partial lateral slots toward theproximal end of the outer tube 710 can be about 0.3 inches while thosepartial lateral slots 716 nearer the distal end of the outer tube 710can be spaced about 0.15 inches apart. The spacing can change in a stepfunction, it can change gradually moving from one end of the outer tube710 to the other, or it can increase and decrease one or more times togenerate certain specific flexibility characteristics. Increased spacingincreases the minimum radius of curvature achievable by compression ofthe partial lateral slots 716 while decreased spacing allows for asmaller minimum radius of curvature.

The number of lateral cuts 716 or, optionally, the number of lateralcuts 716 with T-cuts 718, can number between about 4 and about 50 with apreferred number being between about 6 and about 25 and a more preferrednumber of about 8 to about 15. In the illustrated embodiment, there are12 partial lateral cuts 716, each modified with a “T” slot 718. In otherembodiments, the partial lateral cuts 716 can be shaped differently. Forexample, the partial lateral cuts 716 can be at angles other than 90degrees to the longitudinal axis, curved, V-shaped, Z-shaped, W-shapedor the like. In other embodiments, the ‘T’ slots 718 can have, forexample, further cuts approximately lateral to the longitudinal axis,along any portion of the “T” cut 718.

The outer tube 710 can have an outer diameter of about 0.020 to about0.1 inches with a preferred outside diameter of about 0.040 to about0.060 inches and a more preferred diameter of about 0.045 inches toabout 0.055 inches. In the illustrated embodiment, the outside diameteris about 0.048 inches while the inner diameter is about 0.036 inches.The inside diameter of the outer tube 710 can range from about 0.0.010inches to about 0.090 inches.

FIG. 7B illustrates an embodiment of a side view, in partial breakaway,of the distal end of an axially elongate intermediate tube 720,comprising a lumen 724, a proximal, uncut portion 722, a longitudinalslot 726 further comprising an angled lead in 728, a free side 734, apusher or connected side 732, and a distal tip 730. The distal tip 730interconnects the free side 734 and the pusher side 732. The distal tip730 further comprises a tapered distal end that can be beveled orotherwise shaped into a sharp edge such as by circumferentially forminga trephine-like (cylindrical) blade or even a pointed end that is closedor partially closed. The free side 734 and the pusher side 732 aregenerally integrally formed but can also be affixed to each other bywelding, adhesives, fasteners, or the like.

The lead in 728 to the longitudinal slot 726 is beneficially angled toprevent guidewires, stylets, or other catheters, which are insertedthrough the central lumen 724 from being caught or bumping against anedge. The angled lead in 728 serves a guide to assist with traverse of astylet, obturator, or guidewire past the lead in 728 and into the distalregion of the steerable transseptal needle. The lead in 728 can beangled from between about −80 degrees (the angle can be retrograde) fromthe longitudinal axis (fully lateral) to about +2 degrees and preferablyfrom about +5 degrees to about +20 degrees with a most preferred angleof about +8 degrees and about +15 degrees. In the illustratedembodiment, the angle of the lead in slot 728 is about 10 degrees fromthe longitudinal axis. A second feature of the lead in 728 is that it bepositioned or located proximally to the most proximal “T” slot 718 inthe outer tube 710 when the two tubes 710, 720 are affixed to each other(see FIG. 9 ). The lead in 728 is located at least 1-cm proximal to theproximal most “T” slot 718 and preferably at least 2-cm proximal to theproximal most “T” slot 718 so that bending in the distal region does notdistort the lead in 728 and cause kinking, misalignment, or pinching ofthe internal lumen 724.

The inner or intermediate tube 720 can have an outside diameter that isslightly smaller than the inside diameter of the outer tube 710 so thatthe intermediate tube 720 can be constrained to move longitudinally oraxially within the outer tube 710 in a smooth fashion with relativelylittle force exerted. In the illustrated embodiment, the outsidediameter of the intermediate tube 720 is about 0.033 inches giving abouta 0.0015 inch radial clearance between the two tubes 710 and 720. Theinside diameter of the intermediate tube 720 can range from about 0.002to about 0.015 inches less than the outside diameter of the intermediatetube 720. In the illustrated embodiment, the wall thickness of theintermediate tube is about 0.006 inches so the inside diameter of theintermediate tube is about 0.021 inches. The lumen 724 of theintermediate tube 720 can be sized to slidably accept a stylet orobturator 140 such as illustrated in FIGS. 1 and 2 . A typical styletwire 140 can range in diameter from about 0.01 to about 0.23 inches witha preferred diameter range of about 0.012 to about 0.020 inches. Inanother embodiment, the outer tube 710 has an outside diameter of about0.050 inches and an inside diameter of about 0.038 inches. In thisembodiment, the inner tube 720 has an outside diameter of about 0.036inches and an inside diameter of about 0.023 inches. The radial wallclearance between the inner tube 710 and the outer tube 720 is about0.001 inches and the diametric clearance is about 0.002 inches. Theannulus between the two tubes must be substantially smooth, free fromburrs, and free from contamination because the two tubes 710, 720beneficially need to translate along their longitudinal axis relative toeach other over relatively long axial distances of about 50 to about150-cm.

The inner tube 720 transmits force along its proximal non-slotted region722 from the proximal end of the inner tube 720 to the lead in 728 wherethe force continues to be propagated along the connected side 732 to thedistal end 730. The outer tube 710 transmits force along its proximalnon-slotted region 712. Longitudinal forces applied to the distal,flexible region with the slots 716 cause deformation of the outer tubein an asymmetrical fashion with the side of the outer tube 710comprising the partial lateral slots 716 forming an outer curve if theslots 716 are expanded and an inside curve if the slots 716 arecompressed. Forces to cause bending are preferably exerted such that thepartial lateral slots 716 are compressed up to the point where the gapcloses, but no further, however forces can also be exerted to expand theslots 716, however limits on curvature are not in place because thelateral slots 716 can open in an unrestrained fashion except for thematerial properties of the outer tube 710.

The disconnected side 734 of the inner tube 720, separated from theconnected side 732 by the longitudinal slot 726 and the lead in 728,serves to maintain an undistorted tube geometry and provide resistanceto deformation while helping to maintain the inner lumen 724 in a roundconfiguration and provide a shoehorn or funnel effect to guide anobturator, guidewire, or stylet 140 therethrough as they are advanceddistally. The disconnected side 734, being separated from the forcetransmitting member 722 cannot provide any substantial longitudinal loadbearing structure, although at its distal end, where it is integral oraffixed to the distal end 730, some tension load carrying capabilityexists. The intermediate tube 720 can be considered a split tube anddoes not carry a load in compression or tension along substantially theentire length of the disconnected side 734.

The partial lateral slot 716 in the inner tube 720 and the T-Slot 718 inthe outer tube 710, as well as the longitudinal slot 726 in the inner orintermediate tube 720, and the lead in slot 728 can be fabricated bymethods such as, but not limited to, electron discharge machining (EDM),wire EDM, photoetching, etching, laser cutting, conventional milling, orthe like. In other embodiments, different slot configurations can alsobe employed, such as curved slots, complex slots, zig-zag slots, or thelike. In some embodiments, the partial lateral slot 716 can beconfigured with a tongue and groove or dovetail design to prevent orminimize lateral movement or torqueing of the outer tube 710 in theflexible region. In some embodiments, the tongue and groove or dovetail(not shown) can be generally centered between two “T” slots, forexample. The parts can be ganged and fixture such that, using wire EDM,for example, a plurality of tubes can be cut to reduce manufacturingcosts. As many as 20 to 30 tubes, or more, can be fixed, secured, andetched by the aforementioned methods.

FIG. 8 illustrates a side, cross-sectional view of an embodiment of ahub end 800 of an articulating septal punch. The hub end 800 comprisesthe outer tube 710, the intermediate tube 720, a hub body 802, astopcock petcock 804 further comprising a petcock handle 808 and apetcock through bore 806, a Luer lock fitting 812, an arrow pointer 810,a keyed lumen 834, a setscrew or pin 820, a jackscrew body 816 furthercomprising a plurality of threads 828 and a central lumen 832, a controlknob 814 further comprising a plurality of threads 818, a central lumen830, the protrusion 838, and a circumferential recess 822, an outer tubeweld 824, an orientation mark 840, and an intermediate tube weld 826.The hub body 802 can further comprise a plurality of recesses orcomplementary structures 836. The petcock 804 is affixed to the petcockhandle 808 by welding, integral fabrication, fasteners, adhesives, orthe like. The petcock 804 is retained within a lateral through bore inthe hub body 802, which is in the illustrated embodiment, tapered, usinga locking “C” washer, fastener, screw, pin, or the like (not shown). Thepetcock 804 can be rotated about its longitudinal axis to align thethrough bore 806 with the axis and central lumen of the hub body 802 orit can be rotated sideways to shut off and seal the lumen against theflow of fluids. The Luer lock 812 can be affixed to, or integrallyfabricated with, the hub body 802. The knob 814 is retained within thehub body 802 by the setscrew of pin 820 which prevents axial movementbut permits rotational movement as constrained by the setscrew,projection, or pin 820 riding within the circumferential recess 822which is integrally formed or affixed to the knob 814. The jackscrewbody 816 is capable of axial movement within the hub body 802 but isrestrained from rotation about the long axis by flats or features on theexterior of the jackscrew body 816 which are constrained by flats orfeatures in the keyed lumen 834. The knob 814 comprises threads 828 onits internal lumen which engage with external threads 818 on thejackscrew body 816. Rotation of the knob 814 thus causes the jackscrewbody 816 to move axially proximally or distally with mechanicaladvantage. Rotation of the knob 814 can be forced using manual action orusing a motor or other mechanism (not shown). The outer tube 710 isaffixed to the jackscrew body 816 by the outer tube weld 824. Theintermediate tube 720 (which can also be called the inner tube) isaffixed to the hub body 802 by the intermediate tube weld 826. Thecentral lumen 724 of the inner tube 720 is operably connected to acentral lumen of the hub body 802, the petcock through bore 806, and thelumen of the Luer fitting 812.

The knob 814 can comprise markings 840 to permit the user to visualizeits rotary or circumferential position with respect to the hub body 802.These markings 840 can comprise structures such as, but not limited to,printed alphanumeric characters (not shown), a plurality of geometricshapes such as dots, squares, or the like, or the markings can compriseraised or depressed (embossed) characters of similar configuration asdescribed for the printed markings. In an embodiment, the knob 814 cancomprise a number on each of the facets so the facets can be numberedfrom one to 6, in the illustrated embodiment. The knob markings 840 canfurther comprise raised structures, as illustrated, which can further beenhanced with contrasting colors for easy visualization.

The knob 814 can further comprise one or more complementary structuresaffixed or integral thereto, such as a plurality of protrusions 838 thatfit into detents 836 affixed or integral to the proximal end of the hubbody 802. Such protrusions extending into detents in the hub body 802can provide a ratcheting or clicking sound as well as providingresistance to inadvertent movement of the knob 814 once it is rotated tothe correct location. The knob 814, in some embodiments, can be biasedtoward the hub body 802 to ensure that complementary structures such asthe protrusions and detents come into correct contact. In otherembodiments, the knob 814 can comprise a ratchet system to furthercontrol its rotary movement with respect to the hub body 802. In otherembodiments, the knob 814 can comprise one or more detents (not shown)while the hub body 802 can comprise one or more complementaryprotrusions (not shown). It is beneficial that the knob 814 be movedonly when required by the user and not by accident or not when it isrequired to maintain its rotary position and, by consequence, thecurvature at the distal end of the tubing. The number of ratchetlocations, or low energy positions or setpoints, can range from about 2per 360 degree rotation to about 20 with a preferred number of ratchetlocations ranging from about 4 to about 12.

The hub body 802 can be fabricated from biocompatible metals such as,but not limited to, stainless steel, titanium, nickel coated brass,cobalt nickel alloy, and the like, although it could also be fabricatedfrom polymeric materials in a less expensive format. The knob 814 can befabricated from the same metals as the hub body 802 but it canbeneficially be fabricated from biocompatible polymers such as, but notlimited to, polyamide, polyimide, polyvinyl chloride (PVC),acrylonitrile butadiene styrene (ABS), acetal polymers, polycarbonate,polysulfone, PEEK, Hytrel®, Pebax®, and the like. The petcock 804 andpetcock handle 808 can be fabricated from the same materials as the knob814, or it can be different materials. The jackscrew body 816 can befabricated from the same materials as the hub body 802, or fromdifferent materials, but must be able to be strongly affixed to theouter tube 710.

FIG. 9 illustrates a side view, in partial breakaway, of an embodimentof a distal end 900 of an articulating trans-septal punch with anystylets removed. The distal end 900 comprises the outer tubing 710further comprising the lateral partial slits 716 and the intermediate(or inner) tubing 720 further comprising the longitudinal slit 726 andthe distal tip 730. A weld 902 affixes the distal end of the outertubing 710 to the connected side 732 of the inner tube 720. The distalend 900 can further comprise one or more separate radiopaque markers904. The outer tube 710 and the inner tube 720 are rotated about thelongitudinal axis such that the connected side 732 of the intermediatetube 720 is generally aligned with, and affixed or welded 902 to, theouter tubing 710 on the side comprising the partial lateral slits 716.The flexible region of the inner tube is disposed within the flexibleregion of the outer tube, within the longitudinal extent of the flexibleregion of the outer tube. The width of the partial lateral slits 716,the T-slots 718, and the longitudinal slot 726 can range from about0.001 to about 0.050 inches with a preferred range of about 0.005 toabout 0.020 inches. In the illustrated embodiment, the slits 716, 718,and 726 are about 0.010 inches. The width of the partial lateral slits716 on the outer tube 710 can be used, in compression to provide atleast some limit to how much the outer tube 710 can bend in compressionalong the side comprising the partial lateral slits 716. Note that theintermediate tube 720 extends beyond the distal end of the outer tube710. In the illustrated embodiment, the intermediate tube 720 extendsabout 10 mm to about 20 mm beyond the distal end of the outer tube 710.This construction provides for reduced device complexity, increasedreliability of operation, and reduced manufacturing costs relative toother steerable devices. The system also provides for high stiffnesswhen the distal end 900 is straight, as illustrated, curved as in FIG.11 , or curved, bent, deflected, steered, or otherwise deformed in anyconfiguration between straight and maximally curved. The articulatingtrans-septal punch is necessarily stiff, has high column strength, andhas significant resistance to bending from external sources because itneeds to force an incision through tissue at the end of a very long, 2to 4 foot length, of very small diameter punch tubing. Thus, theall-metal tubing punch can translate forces from its proximal end to itsdistal end that a polymeric catheter could not come close to equaling.Catheters carrying such a punch would be less effective for the specificpurpose of transseptal puncturing than would the articulatingtrans-septal needle.

The distal end 900 of the articulating trans-septal punch is generallyfabricated from metals with sufficient radiopacity or radio-densenessthat they are clearly visible under fluoroscopic or X-ray imaging.However, if this is not the case, additional radiopaque markers 904 canbe affixed to the outer tube 710, the inner tube 720, or both. Theseradiopaque markers can comprise materials such as, but not limited to,tantalum, gold, platinum, platinum iridium, barium or bismuth compounds,or the like.

Close tolerances between the internal diameter of the outer tube 710 andthe outside diameter of the inner tube 720, ranging from a radial gap ofbetween about 0.0005 inches to about 0.008 inches, depending on diametercause the two tubes 710 and 720 to work together to remain substantiallyround in cross-section and not be ovalized, bent, kinked, or otherwisedeformed. This is especially important in the flexible distal regioncomprising the partial lateral cuts 716 on the outer tube 710 and thelongitudinal slot 726 in the inner or intermediate tube 720. The twotubes 710 and 720 can be fabricated from the same materials or thematerials can be different for each tube 710, 720. Materials suitablefor tube fabrication include, but are not limited to, stainless steel,nitinol, cobalt nickel alloy, titanium, and the like. Certain very stiffpolymers may also be suitable for fabricating the tubes 710, 720including, but not limited to, polyester, polyimide, polyamide,polyether ether ketone (PEEK), and the like. The relationship betweenthe inner tube 720, the outer tube 710, and the slots 716, 718, 726, 728serve to allow flexibility and shaping in high modulus materials such asthose listed above, which are not normally suitable for flexibility. Theinternal and external surface finishes on these tubes 710, 720 arepreferably polished or very smooth to reduce sliding friction betweenthe two tubes 710, 720 because of their very small cross-sections andtheir relatively long lengths. Lubricants such as, but not limited to,silicone oil, hydrophilic hydrogels, hydrophilic polyurethane materials,PFA, FEP, or polytetrafluoroethylene (PTFE) coatings can be applied tothe inner diameter of the outer tube 710, the outer diameter of theinner tube 720, or both, to decrease sliding friction to facilitatelongitudinal relative travel between the two tubes which is necessaryfor articulating the flexible, slotted region near the distal end 900 ofthe articulating transseptal sheath. The exterior surface of the outertube 710 can be covered with a polymeric layer, either substantiallyelastomeric or not, which can cover the slots 716, 718, etc. and presenta smoother exterior surface to the environment. The exterior surface canbe affixed or configured to slip or slide over the exterior of the outertube 710.

The weld 902 affixes the outer tube 710 to the intermediate or innertube 720 such that they cannot move relative to each other along thelongitudinal axis at that point. However, since the two tubes 710, 720are affixed to each other on the side of the outer tube 710 containingthe partial lateral slots or gaps 716, compression or expansion of thosegaps 716 can be accomplished by moving the weld 902 by relative movementof the inner tube 720 and the outer tube 710. The weld transmits theforce being carried by the connected side 732 of the inner orintermediate tube 720 to the slotted side of the outer tube 710. Notethat the terms intermediate tube 720 and inner tube 720 are usedinterchangeably, by definition. The inner tube 720 becomes anintermediate tube 720 if another tube or catheter is passed through itsinternal lumen 724.

In other embodiments, since the inner or intermediate tube 720 is split726 lengthwise in the flexible region, a portion, or the entirety, ofthe distal end of the intermediate tube 720 can be affixed, adhered,welded, fastened, or otherwise attached to the outer tube 710 andfunctionality can be retained. The distal end 730 of the intermediatetube 720 can, in some embodiments be retained so as to create acylindrical distal region 730 in the intermediate tube 720 and thisentire cylindrical distal region 730, or a portion thereof that does notproject distally of the distal end of the outer tube 710 can be weldedto the outer tube 710 around a portion, or the entirety of thecircumference of the outer tube 710. If only a portion of the inner tube720 is welded to the outer tube 710, then the weld is beneficiallylocated, approximately centered, on the side of the outer tube 710comprising the partial lateral slots 716. The cylindrical distal region730 is a beneficial construction, rather than completely cutting theinner tube 720 away on one side, since the distal region 730 projectsdistally of the distal end of the outer tube 710 to form the tip of thepunch further comprising a sharpened tip 1102, 1302 configured to punchthrough myocardial tissue (refer to FIGS. 11 and 13 ).

In some embodiments, one of the welds, all of the welds, or a portion ofthe welds can be completed using techniques such as, but not limited to,TIG welding, laser welding, silver soldering, fasteners, adhesives,plasma welding, resistance welding, interlocking members, or acombination thereof. Laser welding is beneficial because it is highlyfocused and can be located with high accuracy. These welds include theweld 902 at the distal end that connects the inner tube 720 and theouter tube 710 as well as the welds at the proximal end connecting theinner tube 720 to the hub and the outer tube 710 to the traveler of thejack-screw 816.

FIG. 10 illustrates an oblique external view of an embodiment of theproximal end 800 of the steerable trans-septal needle comprising theouter tube 710, the knob 814, the hub body 802, the arrow pointer 810further comprising the pointed end 1004, a stopcock body 1006, thepetcock 804, the petcock handle 808, and the Luer fitting 812 furthercomprising a locking flange 1002. The pointed end 1004 can be integrallyformed with the arrow pointer 810, or it can be affixed thereto. Thearrow pointer 810 can be integrally formed with the hub body 802, or itcan be affixed thereto using fasteners, welds, adhesives, brazing,soldering, or the like. The stopcock body 1006 can be integrally formedwith the hub body 802 or it can be affixed thereto using fasteners,welding, soldering, brazing, adhesives, threads, bayonet mounts, or thelike. Referring to FIGS. 8 and 10 , the lumen of the Luer fitting 812 isoperably connected to the through bore of the petcock 804 if the petcock804 is aligned therewith (as illustrated), or the petcock 804 can berotated about an axis to misalign the through bore of the petcock 804with the Luer fitting 812 and prevent fluid flow or passage of solidmaterial therethrough. The knob 814 can be round, shaped as a lever, itcan comprise knurls, facets (as illustrated), or it can comprise aplurality of projections which facilitate grabbing and rotation by theuser. Circumferential motion of the knob 814 about is longitudinal axisis preferably and beneficially smooth but with sufficient friction tomaintain its position in any desired configuration.

FIG. 11 illustrates an embodiment of the distal end 900 of thearticulating trans-septal needle in a curved configuration. The distalend 900 comprises the outer tube 710, the intermediate tube 720, theouter tube lumen 714, the distal end of the proximal region of outertube 712, the distal end 730 of the intermediate tube 720 furthercomprising the sharpened distal tip 1102, the plurality of outer tubelongitudinal cuts or slots 718, and the plurality of outer tube partiallateral cuts 716. The outer tube partial lateral cuts 716 representspaces that close up when the side of the tube in which the lateral cuts716 are located is placed in compression. Such compression is generatedby pushing the outer tube 710 distally relative to the intermediate tube720. When the partial lateral cuts 716 gaps close, further compressionis much more difficult because the outer tube 710 stiffens substantiallywhen no further gap exists for compression. The composite structure,with the intermediate tube 720 nested concentrically inside the outertube 710 is relatively stiff and resistant to kinking no matter whatamount of curvature is being generated. Such stiffness is essential whenusing the articulating trans-septal needle to bend or steer anothercatheter such as a Mullins introducer, or other guide catheter.

Preferred radius of curvatures for the distal end can range from about 1inch to about 6 inches, with a preferred range of about 2 inches toabout 4 inches and a more preferred range of about 2.5 to about 3.5inches for the purpose of puncturing the atrial septum. Even smallerradius of curvatures would be appropriate in, for example, thecerebrovasculature, the arteries of the heart, and the like. The radiusof curvature need not be constant. In some embodiments, the proximal endof the flexible region can have the partial lateral cuts spaced morewidely than those at the distal end of the flexible region, causing thedistal end to bend into a tighter radius than, the proximal end of theflexible region. In other embodiments, the distal region can be lessflexible than the proximal end of the flexible region.

The partial lateral cuts 716, and the “T”-slots in the outer tube 710are beneficially treated using etching, electropolishing, passivation,sanding, deburring, machining, or other process to round the externaledges of the partial lateral cuts 716. Thus, the edges are blunted orrounded so they are not sharp such as to cause the articulatingtrans-septal needle to dig, skive, or shave material from the inside ofa polymer guide catheter since that is a primary benefit of using thearticulating trans-septal needle rather than a pre-curved,non-articulating, trans-septal needle or other punch that, when advanceddistally through a polymeric sheath, can scrape or skive material fromthe inner diameter of the sheath or introducer.

The distal end 1102 can be sharp in some embodiments but it can also besomewhat or completely blunted. In the case of partially or completelyblunted distal construction, the distal end can be operably connected toa source of electrical or radiofrequency (RF) energy and puncture holescan be created using the electrical or RF energy. The energy is carriedby the intermediate tube 720, which is preferably electrically insulatedfrom the outer tube 710, from the hub 900 into which electrical or RFenergy can be applied to the distal tip 1102.

FIG. 12A illustrates a top view of another embodiment of an outer tube1200 in the region of the distal, flexible section, wherein the outertube 1200 comprises a plurality of partial lateral cuts or slots 1206further comprising a dovetail 1202. The dovetail 1202 creates a groove1202 and further comprises a peg or projection 1204 that rides or iscircumferentially constrained within the groove 1202 as long as theouter tube 1200 is neutrally forced, or forced in compression on theside of the partial lateral cuts or slots 1206. The projection 1204riding within the dovetail groove 1202 provides for torque resistanceand torsional rigidity in the area of the dovetail 1202.

FIG. 12B illustrates a side view of the outer tube 1200 in the region ofthe distal, flexible section, wherein the outer tube 1200 comprises thepartial lateral slots 1206, the dovetail 1202 further comprising theprojection 1204, and the “T” slots 718. The T-slots 718 are optional orthey can be configured differently.

The punch can be used to create holes in various structures in the body.It is primarily configured to serve as an articulating or variabledeflection Brockenbrough needle. However, the steerable punch can beused for applications such as transluminal vessel anastomosis, biopsyretrieval, or creation of holes in hollow organs or lumen walls. Thepunch can be used in the cardiovascular system, the pulmonary system,the gastrointestinal system, or any other system comprising tubularlumens, where minimally invasive access is beneficial. The punch can beconfigured to be coring or non-coring in operation, depending on theshape of the distal end and whether an obturator or the circular hollowend of the punch is used to perform the punching operation. In thecoring configuration, a plug of tissue is removed using, for example, acylindrical cutting blade at the distal end, while in the non-coringconfiguration, substantially no tissue is removed from the patient. Thepunch facilitates completion of transseptal procedures, simplifiesrouting of the catheters, minimizes the chance of embolic debris beingdislodged into the patient, and improves the ability of the cardiologistto orient the punch for completion of the procedure. The punch of thepresent invention is integral and steerable. It is configured to be usedwith other catheters that may or may not be steerable, but the punchdisclosed herein does not require external steerable catheters orcatheters with steerability to be steerable as it is steerable orarticulating on its own. The punch is capable of bending and unbending apractically unlimited number of times. The punch is especially usefulwith catheters that are not steerable since the punch comprises its ownsteering system.

The punch can be removed from the lumen of a catheter after it completesperforation of the hollow organ or vessel wall, through which it isplaced, so as to maximize the size of said lumen and allow foradvancement of devices such as diagnostic mapping catheters, ablationcatheters, catheters to place atrial appendage closure devices, mitralvalve repair devices, mitral valve replacement devices, annuloplastyrings, and the like. Without removal of the punch, the lumen iscompromised and the capacity of the sheath to introduce catheters isreduced, given a certain outside diameter. Minimizing the outsidediameter of the sheath is important in preventing a damaged fossaOvalis. This device is intended for use with catheters and is notintended for use as integral to a catheter. This device steers itselfand can steer a catheter but is not a replacement for a steerablecatheter. For instance, an introduction sheath or guide catheter can besteered and bendable but if the trans-septal punch is not steerable andis pre-bent, advancement of the pre-bent trans-septal punch through thesheath or guide catheter and its obturator, steerable or not, will causethe sharp distal end of the trans-septal punch to shave or skive offdebris or material from the inside diameter of the obturator of thesheath or guide catheter or the catheters themselves. This shaving orskiving can occur even when the trans-septal punch is protected by acentral obturator, stylet, inner tube, or guidewire. Use of a steerableobturator does not help the situation because a pre-bent, trans-septalpunch, advanced through a straight, steerable obturator will still shaveoff or skive material from the inside diameter of the obturator.

The steering mechanism disclosed herein in FIGS. 7A & 7B through-FIG. 11can be used to steer other types of catheters, guide catheters,introducers, sheaths, guidewires, or even obturators that are placedwithin the aforementioned devices, with high degree of control over longlengths up to 250 cm or more while requiring less wall thickness andthus allowing for larger internal lumens than steerable devices of theprior art with the same outside diameter. Typical sheaths can haveinternal lumens with capacities of, for example, 6-Fr to 12-Fr and stillmaintain very thin walls of around 1-Fr. While smaller catheters orguide catheters with lumens in the range of about 2-Fr to 5-Fr can haveeven smaller wall thicknesses, depending on the materials used toconstruct the walls of the sheath. Some sheath constructions cancomprise composite materials such as an inner tube fabricated from metaland an outer tube fabricated from metal with a polymeric exteriorcoating. The inner tube can further be coated with an interior liner of,for example PTFE, or other fluoropolymers (PFA, FEP), Parylene, Pebax®,Hytrel®, polyimide, polyamide, PET, or the like, to create certainreduced frictional properties, electrically insulating properties, orboth. These coatings or liners can range in thickness from about 0.0001to about 0.005 inches, with a preferred thickness range of about 0.0005to 0.002 inches. Electrical insulating properties are important ifelectrically conductive catheters are inserted through one or morelumens of a guide catheter or introducer whose mechanical properties arederived from high strength materials such as, in certain embodiments,conductive metal. Electrical insulating properties are also importantshould the device itself be used for electrical purposes such as, butnot limited to, RF Ablation, RF hole puncturing, RF coagulation, and thelike.

The steering mechanism disclosed herein, comprising two or more nestedaxially elongate cylindrical tubes moving relative to each other onlyalong the longitudinal axis, can provide a high degree of precision,repeatability, force, column strength, torsional control, and the like,in a configuration with extremely thin walls and large inside diameter(ID) to outside diameter (OD) ratio. One of the tubes comprises partiallateral cuts or complex lateral gaps and the other tube comprising asplit running substantially the length of the flexible region. Thedisconnected side of the slit tube can be removed so that only apartially formed, connected side remains. However, in preferredembodiments, the disconnected side, which is actually retained at thedistal end, is not removed but serves to fill space within the lumen ofthe outer tube 710 to prevent kinking, improve column strength, preventlumen collapse and provide for guiding of central stylets or catheters.Prior art devices require greater wall thickness, which reduces the sizeof the internal lumen relative to a given outside diameter, or they donot have the same degree of precise movement at the distal tip undercontrol from the proximal end of the device.

FIG. 13 illustrates a side view of the distal end 900 of an articulatingtransseptal punch advanced through a central lumen 1312 of a dilator orobturator 1310 of a guide catheter 1314. The articulating transseptalpunch distal end 900 comprises the outer tube 710, comprising theplurality of partial lateral cuts 716, and the inner tube 720,comprising a sharpened distal tip 1302. The sharpened distal tip 1302comprises a bevel 1304, one or more facets 1308, a point 1318, and arounded or blunted outside edge 1306. The obturator 1300 furthercomprises the central lumen 1312. The guide catheter 1314 furthercomprises a central lumen 1316. The guide catheter 1314 and itsobturator 1310 are generally curved near the distal end. When the distalend 900 is advanced distally through the lumen 1312 of the obturator1310, scraping of the inner wall of the obturator 1310 is prevented byinclusion of a rounded edge 1306 of the distal end 1302 toward theoutside of the curvature. The distal sharp end 1302 comprises a bevel1304 to create a sharpened tissue punch with a point 1318. The facets1308 are optional but can be provided in numbers ranging from one toabout 10. The bevel 1304 can be generated at a single angle, or with acomplex curvature. In some embodiments, the bevel 1304 can be generatedat an angle of about 20 to about 80 degrees from lateral to the axis ofthe tube with a preferred range of about 30 to about 60 degrees fromlateral, and a most preferred range of about 40 to about 50 degrees. Thepoint 1318 can be a point in three dimensions or in two dimensions, suchas the point 1318 illustrated herein.

FIG. 14 illustrates the distal end 900 of an articulating transseptalpunch further comprising a stylet 1400. The stylet comprises the corewire 1402, the proximal lock 1404 (not shown), a collapsing shield 1408,and the rounded distal tip 1406. The stylet 1400 is slidably andremovably inserted through the central lumen of the inner tube 720 toassist with blunting the sharpened distal end. Stylets sufficientlysmall to fit through these central lumens of the inner tube 720 aregenerally quite small, having a diameter of about 0.012 to 0.015 inchesand are necessarily very weak. They are subject to bending and kinkingand cannot hide a sufficient amount of the distal pointed end 1302 toprevent damage to the inside of a polymeric guide catheter 1314 or itsobturator 1310. Because the inner tube 720 has a very thick wallrelative to its overall diameter, a wire inserted through the centrallumen of the inner tube 720 cannot protect or shield the distal end 1302adequately. Thus, a regular stylet 1400 is only partially useful inpreventing skiving material from the inside of the guide catheter 1314or obturator 1310 unless it includes the collapsing shield 1408. Aradially collapsing feature 1408 of the obturator 1400 can be beneficialin protecting the distal end with more completeness than anon-collapsing version. The collapsing feature 1408 is collapsedradially, laterally, or diametrically by withdrawing the obturator 1400inside the inner tube 720 and it expands on its own using self expansionunder spring bias, shape memory recovery, or the like. The obturator1400 can be fabricated from materials such as, but not limited to,stainless steel, nitinol, cobalt nickel alloy, titanium, and the likeusing methods such as cold rolling or tempering to achieve substantialspring conditions. In the illustrated embodiment, the collapsing shieldfeature 1408 is created by means of a split tube of spring stainlesssteel, comprising a plurality of slots or openings 1410 which are biasedoutward to create a bulge when unrestrained. The slotted tube shield1408 is integral or affixed to the core wire 1402. The amount of outwardbulge of the shield 1408 is not large but is sufficient to substantiallyequal or exceed the wall thickness of the inner tube 720.

In some embodiments, the outer tube 710 can be modified to adjuststiffness. It can be preferential to increase the resistance to bendingmoving distally to proximally on the outer tube 710. This increase inbending resistance contravenes the tendency of the outer tube to bendmore severely at the proximal end of the flexible region than in thedistal region. It is possible to configure the bending so that the bendradius is approximately constant or such that a greater curvature(smaller radius of bending) is generated moving toward the distal end ofthe flexible region. The partial lateral slots 716 can be cut withreduced depth more proximally to increase the resistance to bendingimparted by the outer tube 710. The partial lateral slots 716 can be cutmore narrowly in the more proximal regions to reduce the distance theslot 716 can close. The T-slots 718 can be reduced in length or removedin the more proximal regions of the flexible region of the outer tube710. Elastomeric bumpers or fillers can be added to some of the partiallateral slots 716 to reduce the amount the partial lateral slots 716 cancompress. Once the partial lateral slots 716, associated with theT-slots 718 have closed under bending of the outer tube 710, furtherbending is resisted and is substantially arrested. By tailoring thewidth and spacing of the partial lateral slots 716, a specific finalcurvature can be tailored for a given catheter.

FIG. 15A illustrates an the outer tube 710 comprising the lumen 714, theproximal tube wall 712, the plurality of partial lateral slots 716, theplurality of T-slots 718, a short partial lateral slot 1502, a slightlylonger partial lateral slot 1504, and a standard length lateral slot 716but with a shortened T-slot 1506. The most proximal partial lateral slot1502 penetrates less than the standard partial lateral slots 716. Thesecond (moving distally) partial lateral slot 1504 is slightly longerthan slot 1502 and therefore is more flexible in that region andrequires less force to generate bending. The third partial lateral slotcomprises the shortened T-slot 1506 which reduces the ability of thetubing to bend given a constant bending force.

FIG. 15B illustrates the inner tube 720 comprising the lumen 724, theproximal region 722, the connected side 732, the distal end 730, thesharpened tip 1302, and a beveled lead-in 1510 at the proximal end ofthe distal end 730. The proximal end of the disconnected region can bemoved distally to increase the stiffness of the inner tube 720 in aspecific region, generally the most proximal part of this distal,flexible region.

Since, during use of the steerable transseptal needle, the needle isadvanced distally through an already placed introducer, sheath, or guidecatheter, it is beneficial that the straight steerable transseptalneedle be capable of advancing through any curvatures in the alreadyplaced introducer, sheath, or guide catheter. Thus. In certainembodiments, the bevel is oriented such that the pointed point of thesharpened tip 1302 is oriented toward the direction of bending. In thisway, the steerable transseptal needle, when in its straightconfiguration, can be pushed against into the curved region of theintroducer, sheath, or guide catheter and not have the sharp point diginto the wall of the introducer, sheath, or guide catheter. The side ofthe sharpened tip 1302 away from the sharp point can further be roundedsomewhat to make it even more atraumatic and smooth so it can skate orsled along the curvature of the introducer, sheath, or guide catheterwithout digging out any material from the wall of the introducer,sheath, or guide catheter.

In certain preferred embodiments, it is beneficial that the inner tube720 can sustain compression to generate bending of the outer tube 710 atthe distal end back to straight after being curved and even to bendbeyond straight in the other (or opposite) direction. In order tosustain compression, it is beneficial that the disconnected side 734 beseparated from the connected side 732 at or near substantially thecenter or midpoint of the tubing. Depending on the width of the slot 726separating the disconnected side 734 from the connected side 732, thelocation of the slot can be offset from the midpoint but this isdependent on the wall thickness of the inner tube 720 and the angle ofthe slotting. In a preferred embodiment, interference exists between thedisconnected side 734 and the connected side 732 such that thedisconnected side and force transmitting member cannot movesubstantially inward, a situation that would have negative effects ofobstructing the lumen, restricting fluid flow therethrough, trappingstylets or other catheters that need to move longitudinally therein, orbuckling sufficiently to prevent application of longitudinal compressionforces on the connected side 732.

FIG. 16A illustrates a lateral cross-sectional view an inner tube 720nested inside an outer tube 710 and separated from the outer tube 720 bya radial gap 1602 in the flexible region of an articulating septal punchwherein the inner tube 720 is separated by a split or gap 726 into twoapproximately or substantially equal parts, a connected side 732 and adisconnected side 734, approximately (or substantially) at the midlineor centerline of the cross-section.

FIG. 16B illustrates a lateral cross-sectional view an inner tube 720nested inside an outer tube 710 and separated from the outer tube 720 bya radial gap 1602 in the flexible region of an articulating septal punchwherein the inner tube 720 is separated by a split or gap 726 into twosubstantially unequal parts, a connected side 732 and a disconnectedside 734, substantially offset from the midline or centerline of thecross-section.

Referring to FIGS. 16A and 16B, the disconnected side 734 is retained inclose proximity to the outer tube 710 by its stiffness and its inabilityto deform such that the edges of the disconnected side 734 can passbeyond the edges of the connected side 732 and thus the two sides 732and 734 are retained radially displaced from centerline. If the gap 726were too large or either side 732, 734 were small enough to fit withinthe edges of the other side, then displacement of one side toward thecenterline and confounding of the off-center orientation of theconnected side 732 or 734 would occur leading to buckling of theconnected side 732 in compression and inability to straighten out a benttransseptal needle. Another problem might be loss of torqueability andpredictability of the direction of bending. Both embodiments shown inFIGS. 16A and 16B maintain circumferential and radial orientation of theinner tube connected side 732 relative to the disconnected side 734 andpromote high precision deflection of the distal tip.

In preferred embodiments, the radial gap 1602 is minimized and isretained between about 0.0005 to 0.002 inches when the needle is about0.050 in outside diameter. Furthermore, the split or gap 726 should beas minimal as possible and in preferred embodiments can range from about0.002 inches to about 0.015 inches with a gap of about 0.004 to 0.010inches being most preferable.

The embodiments presented in FIGS. 7 through 16 describe a system thatdoes not use pull wires or push rods. There are no side lumens requiredin either the outer tube or the inner tube. Such side lumens, as foundin certain prior art catheters, require extensive cross-sectional areabe used to surround the side lumens and take away from the potentialarea for the central lumen since the outside extent of the catheter islimited. The use of control rods or pull wires requires such as those incertain prior art catheters, retaining these structures along one sideof the outer tube so it does not obstruct the lumen, which is needed forstylets, fluid injection, radiopaque dye injection, and the like. Sidelumens or channels are necessary to retain a pull wire or control rod inthe correct location so as to provide correct off center forces to bendthe distal end. The side lumens are also necessary to keep the controlrod or pull wires out of the central lumen which needs to remain openand substantially circular. The system disclosed herein, however,retains a high degree of column strength, maximum torqueability, thelargest possible central lumen, and a very strong control and steeringfunction or capability. Furthermore, the side lumens or channels arenecessary to maintain spatial (rotational orientation) for thearticulating distal end of the device. Without the side lumens orchannels permitting axial slidability but generating radial retention,the pull wires or pushrods would be free to migrate around within thecentral lumen of the device and could bend the device in an unwanteddirection. Long catheters or needles with relatively smallcross-sectional areas are highly subject to torque and rotationalmisalignment and some method must be employed to retain the correctcircumferential location of the articulating apparatus.

Furthermore, a pull-wire as used in prior art devices is incapable ofgenerating compression against the distal end of the device so apull-wire could not, under compression, move or articulate the distalend of the device. The pull-wire, under tension, can move or articulatethe distal end and would require some sort of counterforce such as anopposing pull-wire, shape memory metal, or spring return biasing to movethe distal end in the reverse direction. A pull-wire with a diameter ofabout 0.010 inches (0.0000785 square inches) would sustain tension loadsof about 500,000 PSI, to generate a pull force of 40 pounds or 250,000PSI to generate a pull force of 20 pounds, beyond the capability of mostknown metals or polymers. Forces exceeding 20 pounds can be necessary tocause bending and stiffening of a Brockenbrough needle to generate theappropriate column strength and bending resistance such that the fossaOvalis can be penetrated by the needle. A unconstrained push-rod orcontrol rod of almost any diameter will buckle under these types ofloads and be unable to generate oppositional forces under compression toarticulate the distal end in the reverse direction sufficiently to makethe device clinically acceptable.

However, a tubular or cylindrical central control device can maintainits structure in compression, maintain circumferential location withinthe outer cylindrical, axially elongate tube, maintain precise control,maintain sufficient tensile strength to exert forces up to and exceeding40 pounds, and maintain a central lumen larger than any other type ofsteerable device. The resistance to buckling occurs even when the innertube is slotted longitudinally because the inner tube is constrainedwithin the outer tube using very tight tolerances that will not let theinner tube bend out of its straight orientation, even under compression.

FIG. 17A illustrates a lateral cross-sectional view of the shaft 1700 ofa steerable needle or punch. The shaft comprises an outer tube 710further comprising a lumen 1710, a plurality of control rods 1702, aplurality of control rod spaces 1706, and a resultant central lumen1712. The control rods 1702 are slidably disposed within the lumen 1710outer tube 710, as well as relative to each other. The embodimentillustrated in FIG. 17A has three control rods 1702, which can be pulledfrom the proximal end of the device to exert compression on the outertube, and may optionally be stiff enough to be pushed distally withinthe outer tube to tension the outer tube, or twisted to apply torque tothe outer tube. In some embodiments, one or more of the plurality ofcontrol rods 1702 can be replaced with keepers. The control rods 1702are affixed at their distal end to the outer tube, distal to flexibleregion of the outer tube 710. As illustrated, the control rods arepartial cylinders (hollow, in this case, though they may be solid)disposed in the lumen 1712 radially displaced from the remaining controlrods. Each control rod extends proximally to a proximal hub (illustratedin FIGS. 8 and 40 , for example) and thus remains in a partial cylinderconfiguration from the proximal hub to the point where it is fixed tothe outer tube, distal to the flexible region. Each partial cylinder ischaracterized by a longitudinal axis, corresponding to the axis of thecomplete cylinder to which they relate, and each partial cylinder isdisposed generally coaxially within the outer tube, such that thelongitudinal axis of the outer tube roughly corresponds the longitudinalaxes of the partial cylinders, thus leaving the lumen defined by thepartial cylinders and/or the outer tube open for passage of stylets,needles, or fluids. Each of the control rods 1702 is retained away fromthe resultant central lumen 1712 and held substantially against theinner diameter of the outer tube 710 by remaining control rods and thenarrow spacing 1706. The three control rods 1702 are configured toprovide for steering, deflection, or articulation of the distal end ofthe steerable needle or punch about multiple axes. Each control rod 1702can be moved independently, or in concert, along the longitudinal axisunder the influence of different actuators, controllers, hydraulicactuators, electrical actuators, pneumatic actuators, levers, knobs,jackscrews, or the like.

The outer tube 710, the control rods 1702, or both, can be fabricatedfrom materials such as, but not limited to, polyimide, polyamide,polyester, polyurethane, silicone, PEEK, PTFE, PFA, FEP, stainlesssteel, nitinol, titanium, cobalt nickel alloys, and the like.

FIG. 17B illustrates a lateral cross-sectional view of anotherembodiment of the shaft 1712 of a steerable needle or punch. The shaft1712 comprises an outer tube 710 further comprising a lumen 1710, aplurality of rods 1704, 1720, 1722, and 1724, a plurality of rod spaces1708, and a resultant central lumen 1714. The shaft 1712 furthercomprises a tubular liner 1716, disposed within the lumen remainingwithin rods 1704, 1720, 1722, and 1724, which can serve as a fluid-tightbarrier, or liner, to prevent the migration fluids into or out of thecentral lumen 1718 through the side walls of the inner or outer tube inthe flexible regions (when the flexible regions are formed with slots asillustrated in the Figures). The liner 1716 can be fabricated frommaterials such as, but not limited to, polyimide, polyamide, polyester,polyurethane, silicone, PEEK, PTFE, PFA, FEP, stainless steel, nitinol,titanium, cobalt nickel alloys, and the like. The wall thickness of theliner can range from about 0.0005 inches to about 0.010 inches, with apreferred range of about 0.0007 to about 0.005 inches. The liner 1716can be affixed to the hub (not shown) at the proximal end and to thedistal end of the outer tube 710, either directly or through anintermediary structure which could include a bonding ring or at leastone of the rods 1704, 1720, 1722, and 1724.

In the device of FIG. 17B, rods 1704 and 1720 are control rods whilerods 1722 and 1724 are configured as keepers or stays. As illustrated,the keeper is a partial cylinder (hollow, in this case, though they maybe solid) disposed in the lumen 1712 or 1718 radially opposite ordisplaced from the control rods. The keepers or stays 1722 and 1724 arepreferably disconnected from the control rods 1704 and 1720, and notdirectly attached to the control rods. The keepers or stays 1722 and1724 can be free-floating within the lumen of the outer tube 710 (notfixedly attached to the outer tube or the control rod), or they may beaffixed to the outer tube 710 at the distal end, a point proximal to theflexible region, or a point somewhere intermediate within the flexibleregion, without being directly fixed to the control rods. The keeper orstay 1722 is preferably disconnected from the other keeper or stay 1724such that relative axial motion can occur between the two elements.

The two control rods 1704 and 1720 are preferably adjacent to each otherbut not affixed to each other, again so that relative axial motion canoccur between the two elements. The first control rod 1704 is preferablydisposed at about 90 degrees, or orthogonal, to the cross-sectionallocation of the second control rod 1720. The keepers or stays 1722 and1724 retain the control rods 1704 and 1720 radially outward and awayfrom the center such that the control rods 1704 and 1720 can exertoff-center forces on the distal end of the outer tube 710, as well asoptionally maintaining a lumen for the passage of fluid, instruments, orthe like. The control rods 1704 and 1720 can be affixed to the outertube 710, at a location approximately distal to the flexible region ofthe outer tube.

The control rods 1704 and 1720 can be affixed to control mechanisms atthe proximal end of the steerable catheter, needle, punch or otheraxially elongate medical instrument. The control rods 1704 and 1720 areconstrained to move axially, or longitudinally, within the outer tube710, and relative to each other. The keepers or stays 1722 and 1724preferably do not extend all the way to the proximal end of thesteerable medical device but could do so as long as they are notconnected to other structures. In some embodiments, proximal to theflexible region, only the control rods 1704 and 1720 would exist andcould subtend up to about ½ of the total circumferential arc, each.

In the embodiment shown in FIG. 17B, exerted axial force on control rod1704, relative to the outer tube 710, can cause bending within a planerunning generally midline through the control rod 1704 cross-section.Axial force exerted on the control rod 1720, relative to the outer tube710, can cause bending within a plane running generally midline throughthe control rod 1720 arc. Both compression and tension forces can beapplied to the control rods 1704, 1720 relative to the outer tube 710such that bending in both a positive and negative direction can beperformed using only a single control rod 1704, 1720, rather than acomplementary pair of pull wires, which can operate generally only intension.

In yet other embodiments, only one of the rods 1704, 1720, 1722, 1724 isa control rod and the other rods are keepers. In yet other embodiments,three or four of the rods operate as control rods for bending or otherfunctions to be transmitted from the proximal end to the distal end ofthe axially elongate device. In other embodiments, more than four rodsare comprised by the device with a realistic maximum of 10 to 20 rods. Amajor advantage of using a plurality of disconnected rods ismaximization of bending and flexion within the device tubing.

FIG. 18A illustrates a lateral cross-sectional view of anotherembodiment of the shaft 1800 of a steerable needle or punch. The shaft1800 comprises the outer tube 710 further comprising a lumen 1810, acontrol rod 1804, a control rod retainer 1806, guide, or keeper, aplurality of control rod spaces 1808, and a resultant central lumen1814. The shaft 1800 further comprises a tubular liner 1716, as in FIG.17A. A stylet 1812 is slidably disposed within the fluid impermeablecentral lumen 1818. The control rod 1804 is slidably disposed within thelumen 1810 and retained against or near the internal wall of the outertube 710 by the control rod retainer 1806. The plurality of control rodspaces 1808 between the control rod 1804 and the control rod retainer1806 are intentionally kept as small as possible without generatingexcessive friction that would hinder longitudinal relative movementbetween the control rod 1804 and the control rod retainer 1806, as wellas between the control rod 1804 and the outer tube 710. In theillustrated embodiment, the plurality of control rod spaces 1806 areabout 0.002 inches wide while the radial distance between the outer wallof the control rod and the inner wall of the inner tube is about 0.001inches. These spaces could be increased up to, but not beyond, the pointwhere the retaining function of the control rod retainer 1806 isdefeated and the control rod 1804 can move laterally into the center ofthe lumen 1814. The outer tube 710 is shown with a 0.050 inch OD and awall thickness of about 0.006 inches with a range of about 0.001 to0.020 inches. The control rod 1804 is illustrated with a wall thicknessof about 0.008 inches but can range from about 0.001 to about 0.020inches.

FIG. 18B illustrates a lateral cross-sectional view of anotherembodiment of a shaft 1820 of a steerable needle or punch. The shaft1820 comprises the outer tube 710 further comprising the lumen 1810, twocontrol rods 1822, a control rod retainer 1806, guide, or keeper, aplurality of control rod spaces 1824, and a resultant central lumen1814. A stylet 1812 is slidably disposed within the central lumen 1814.The control rod retainer 1806 can be affixed at the distal end of theouter tube 710, it can be affixed at a hub (not shown), or it can beaffixed to the outer tube at a point intermediate the hub and a flexibleregion in the outer tube 710. In a preferred embodiment, the control rodretainer 1806 is affixed to the outer tube at one axial location only.In another embodiment the control rod retainer 1806 is not affixed tothe outer tube or the inner tube, but rather rides loosely within theouter tube 710 held in place by the control rods 1822. This structureapplies to all the control rods and control rod retainers describedwithin this specification.

The two control rods 1822 are affixed at their proximal end to a hub(not shown) or a control mechanism within a hub (not shown) allowing thecontrol rods 1822 to be independently moved longitudinally, or axially,relative to the outer tube 710, under manual or assisted control. Suchassisted control includes, but is not limited to, rotational electricmotors, pneumatic actuators, stepping motors, linear electric motors,hydraulic actuators, and the like and may further be controlled bycomputers or other automated control systems. The two control rods 1822can, in other embodiments, be one or both affixed directly to the hub,or through an intermediary member, such that any relative motion betweenthe control rods and the outer tube is brought about by moving the outertube by an actuator while the control rods, one or both, remain affixedto the hub, directly or through an intermediary member such as anothertube, anchor, fastener, or the like. Affixation can be performed usingmethods and devices such as, but not limited to, welds, laser welds,silver solder, fasteners, adhesives, mechanical interlock, ultrasonicwelds, or the like.

At the distal end, the control rods 1822 can be affixed directly to theouter tube 710 distal to a region of enhanced flexibility or through anintermediary such as a separate tube, linkage, control rod, fastener, orthe like. The control rods 1822 can be affixed at a same point or atdifferent locations along the circumference or longitudinal axis of theouter tube 710.

FIG. 18C illustrates a side view of a control rod and keeper system 1850comprising a c-cross-sectional shaped control rod 1804 (a half-pipe) anda c-cross-sectional shaped control rod keeper 1806 (also a half-pipe).This configuration is shown in lateral cross-section in FIG. 18A. Thecontrol rod 1804 can extend or run substantially the entire workinglength of the steerable needle between a hub (not shown) and a regiondistal to any deflectable or steerable regions of the outer tube 710(refer to FIGS. 18A and 18B). The control rod 1804 can also beconfigured, as shown, to have a C-shape or half-pipe configuration onlywithin the approximate region of a bendable or articulating region ofthe outer tube 710. In other areas, proximal (1852) and distal (1858) tothe flexible region, the control rod 1804 can be a complete tube orcylinder, or it may continue in the half-pipe or partial cylinderconfiguration for the entire length of the control rod, from itsproximal attachment at the proximal hub to the distal attachment to theouter tube. The control rod 1804 is affixed to, or integral to, a distaltubing extension 1854, which can be optionally terminated with a sharppoint, as shown, or with a rounded blunt end, with a tapered dilator, orthe like. The distal tubing extension 1854 steps up, in the illustratedexample, to a larger diameter at the point 1860. The distal tubingextension 1854 can be integral, or affixed to the control rod 1804 orthe control rod guide 1806 by a weld, adhesive bond, mechanicalfastener, solder joint, brazing joint, or the like.

In the devices of FIGS. 17A through 18C, multi-axis steering isaccomplished with the plurality of control rods. These partial cylindercontrols rods replace the inner tube of the device of FIGS. 7 through 15, and because the control rods can tension the outer tube at radiallydisplaced point, each control rod can be tensioned to bend the flexibleregion across a different plane, or in a different radial direction.

The c-shaped control rod guide or retainer 1806 can be completelydisconnected from the control rod 1804, or it can be affixed at a pointdistal to the flexible region, at a point proximal to the flexibleregion, but not both proximal and distal. In other embodiments, thecontrol rod retainer 1806 can be affixed to the outer tube 710 but notto the control rod 1804. The control rod retainer 1806 serves thefunction of forcing the control rod 1804 laterally off-center tomaintain off-center within the outer tube 710 and for filling the lumenof the outer tube 710 to prevent collapse of the lumen and kinkingduring articulation or bending.

FIG. 19A illustrates a lateral cross-sectional view of anotherembodiment of a shaft 1900 of a steerable needle or punch. The shaft1900 comprises the outer tube 710 further comprising the lumen 1910, oneor more “V” shaped control rod 1902, a resultant central lumen 1910. Astylet 1812 can be slidably disposed within the central lumen 1910. TheV-shaped control rod 1902 can be slidably disposed within the lumen 1910of the outer tube 710 such that it can be axially displaced withoutsubstantial resistance, yet it is still constrained against substantiallateral movement due to the space restrictions within the lumen 1910.

FIG. 19B illustrates a lateral cross-sectional view of anotherembodiment of a shaft 1920 of a steerable needle or punch. The shaft1920 comprises the outer tube 710 further comprising the lumen 1910, oneor more “U” shaped control rod 1922, a resultant central lumen 1910. Thestylet 1812 can be slidably disposed within the central lumen 1910. TheU-shaped control rod 1922 can be slidably disposed within the lumen 1910of the outer tube 710 such that it can be axially displaced withoutsubstantial resistance, yet it is still constrained against substantiallateral movement due to the space restrictions within the lumen 1910.

Referring to all the control rods disclosed herein, these control rodscan extend the entire length of the device from the hub or handle to aregion distal to any flexible regions or regions of enhanced bendabilityin the outer tube. The control rods can also be affixed or integral torods, tubing, or other structures extending part way through the devicebut not traversing the flexible regions or regions of enhancedbendability. The control rods can be affixed to the hub or handle by wayof an anchor, weld, adhesive, mechanical interlock, actuator, or thelike. The control rods can further comprise hinges or areas ofsubstantially increased flexibility proximate one or both of the ends,proximal and distal.

FIG. 20A illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2000 of a steerable needle or punch. The shaft2000 comprises the outer tube 710 further comprising the lumen 1910, oneor more hollow, round control rods 2002, the control rods furthercomprising a resultant central lumen 2004. This arrangement does notleave room for a large diameter, round stylet but it does provide for asubstantial lumen for fluid flow 1910 within the outer tube 710.

FIG. 20B illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2020 of a steerable needle or punch. The shaft2020 comprises the outer tube 710 further comprising the lumen 1910, oneor more hollow, round control rods 2002, and an off-center but full sizestylet 1812. This arrangement does provide for a lumen for fluid flow1910 within the outer tube 710 and the stylet 1812 further provides thefunction of the control rod retainer, when the stylet 1812 is in placewithin the lumen 1910.

FIG. 21A illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2100 of a steerable needle or punch. The shaft2100 comprises the outer tube 710 further comprising the lumen 1910, arectangular control rod 2102, the control rod 2102 further comprising acentral lumen 2104. A round stylet can be retained within the lumen 2104and it does provide for a substantial lumen 1910 for fluid flow withinthe outer tube 710. The distal end of the control rod 2102 can beaffixed to the outer tube 710 on one side or another thus generatingsome offset forces to bend the outer tube 710.

FIG. 21B illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2120 of a steerable needle or punch. The shaft2200 comprises the outer tube 710 further comprising the lumen 1910, andan I-Beam shaped control rod 2122. A round stylet cannot be retainedwithin the lumen 1910 but it does provide for a substantial lumen 1910for fluid flow within the outer tube 710, even greater than that for theembodiment shown in FIG. 21A. Note that the edges of the control rods2122 and 2102 in FIGS. 21A and 21B are rounded to provide a smoother fitwithin the lumen 1910, but this rounding, or even part of it, isoptional.

FIG. 22A illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2200 of a steerable needle or punch. The shaft2200 comprises the outer tube 710 further comprising the lumen 1910, anda round, solid control rod 2202. A round stylet (shown in FIG. 22B) canbe retained within the lumen 1910 by moving the control rod 2202off-center and it does provide for a substantial lumen 1910 for fluidflow within the outer tube 710 but little control over the radial orcircumferential position of the control rod within the outer tube 710 isprovided.

FIG. 22B illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2220 of a steerable needle or punch. The shaft2220 comprises the outer tube 710 further comprising the lumen 1910, anda round, hollow control rod 2222 further comprising a lumen 2204. Thestylet 1812 is retained within the lumen 2204 of the hollow control rod2222.

FIG. 23A illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2300 of a steerable needle or punch. The shaft2300 comprises the outer tube 710 further comprising the lumen 1910, anda round, hollow control rod retainer 2302 further comprising a centrallumen 2304 and a plurality of retainer grooves 2306, and a plurality ofcontrol rods or pull wires 2308. A round stylet (shown in FIG. 22B) canbe retained within the lumen 2304 but is left out of this illustration.The control rods or pull wires 2308 are illustrated as solid but cancomprise structures such as, but not limited to, stranded, tubular,circularly braided, flat braided, continuous tubular, slotted tubular,or the like. The grooves 2306, which can be termed channels, slots, orthe like, are beneficially cut or formed into the exterior of thecontrol rod retainer 2302. In other embodiments, these grooves 2306could be replaced by one or more off-center lumens (not shown) withinthe cross-section of the control rod retainer 2302. The control rodretainer 2302 can be affixed at one or more points within the outer tube710 or it can be free floating. The central lumen 2304 is capable ofaccepting another wire or control rod, a stylet, or fluid.

FIG. 23B illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2320 of a steerable needle or punch. The shaft2320 comprises the outer tube 710 further comprising the lumen 1910, anarcuate or curved, c-shaped control rod retainer 2322 and an arcuate orc-shaped cross-section control rod 2328. The control rod 2328 and thecontrol rod retainer 2322 are separated by a plurality of gaps or spaces2324. A round stylet (not shown here but shown in FIG. 22B) can beretained within the remaining lumen 2326. The spaces 2324 between thecontrol rod retainer 2322 and the control rod 2328 do not radiate fromthe center in a radial direction but rather at an angle from the radialdirection. The spaces 2324 between the control rod retainer 2322 and thecontrol rod 2328 are drawn at about 0.002 inches spacing but thatspacing could be between about 0.0005 and 0.015 inches with a preferablespacing of between about 0.001 and 0.008 inches.

FIG. 24A illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2400 of a steerable needle or punch. The shaft2400 comprises the outer tube 710 further comprising the lumen 1910, anarcuate or curved control rod 2402 which subtends approximately 270degrees of circumference on the inside diameter of the outer tube 710. Around stylet 1812 is illustrated as slidably, and removably, retainedwithin the remaining lumen 1910 which is defined by the curvature in thecenter of the arcuate control rod 2402. The arcuate control rod 2402 isretained against the side wall of the outer tube 710 by its shape, beinggreater than 180 degrees in circumference. Because the arcuate controlrod 2402 is not a full 360 degree control rod, it will have somewhatincreased bending and decreased resistance, relative to a fully circularcontrol rod, to lateral forces imposed thereupon.

FIG. 24B illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2420 of a steerable needle or punch. The shaft2420 comprises the outer tube 710 further comprising the lumen 1910, anarcuate or curved control rod 2428 which subtends approximately 180degrees of circumference on the inside diameter of the outer tube 710,along with an arcuate control rod retainer 2422 which further subtendsapproximately 180 degrees within the outer tube 710. A plurality ofslits, or slots, 2426 separate the control rod 2428 and the control rodretainer 2422.

The control rod retainer 2422 of FIG. 24B is smaller in wall thicknessthan that of the control rod 2428 to permit greater fluid flow ratestherein and still keep the control rod 2428 against the inside wall ofthe outer tube 710 and offset from the centerline.

FIG. 25A illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2500 of a steerable needle or punch. The shaft2500 comprises the outer tube 710 further comprising the lumen 1910, anarcuate or curved control rod 2502 which subtends approximately 180degrees of circumference on the inside diameter of the outer tube 710,along with an arcuate control rod retainer 2504 which further subtendsapproximately 180 degrees within the outer tube 710. A plurality ofslits, or slots, 2506 separate the control rod 2502 and the control rodretainer 2504. This configuration is similar to that shown in FIG. 18Aexcept that the control rod 2502 and the control rod retainer 2504subtend a greater arc than the device of FIG. 18A and thus, the gaps2506 are much smaller, in this case about 0.002 inches and leaving verylittle room for lateral displacement of the control rod 2502. The outertube 710, as shown, is an 18 gauge tube with an outside diameter ofabout 0.050 inches and an inside diameter of about 0.038 inches. Thisdiameter can change to suit the occasion but the concept of tighttolerances between the inner and outer structures is important inretaining alignment and off-center positioning.

FIG. 25B illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2520 of a steerable needle or punch. The shaft2520 comprises the outer tube 710 further comprising the lumen 1910, anarcuate or curved control rod 2522 which subtends approximately 180degrees of circumference on the inside diameter of the outer tube 710,along with an arcuate control rod retainer 2524 which further subtendsapproximately 180 degrees within the outer tube 710. A plurality ofslits, or slots, 2526 separate the control rod 2522 and the control rodretainer 2524. This configuration is similar to that shown in FIG. 25Aexcept that the control rod 2522 and the control rod retainer 2524subtend a significantly reduced arc than the device of FIG. 25A andthus, the gaps 2526 are much larger, in this case about 0.009 inches andleaving much more room for lateral displacement of the control rod 2522.As in FIG. 25A, the outside arc of the control rod 2522 and the controlrod retainer 2524 is a close fit with the inside diameter of the outertube 710, having only a gap of about 0.001 inches. Since the materialsused in all the elements can be metallic, friction from longitudinalrelative translation is low and is not a major factor relative to theforces needed to bend the structure.

FIG. 25C illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2540 of a steerable needle or punch. The shaft2540 comprises the outer tube 710 further comprising the lumen 1910, anarcuate or curved control rod 2542 which subtends approximately 180degrees of circumference on the inside diameter of the outer tube 710,along with an arcuate control rod retainer 2544 which further subtendsapproximately 180 degrees within the outer tube 710. A plurality ofslits, or slots, 2546 separate the control rod 2542 and the control rodretainer 2544. This configuration is similar to that shown in FIG. 25B,with approximately the same slot width 2546, except that the control rod2542 and the control rod retainer 2544 comprise a significantly reducedoutside diameter than the device of FIG. 25B, and thus, the gap 2548between the control rod 2542 and the inside diameter of the outer tube710, as well as that of the control rod retainer and the inside diameterof the outer tube 710 are much larger and leave much more room forlateral displacement of the control rod 2542 and the retainer 2544.

FIG. 26A illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2600 of a steerable needle or punch. The shaft2600 comprises the outer tube 710 further comprising the lumen 1910. Theshaft 2600 further comprises a plurality of solid control rods or wires2602, an intermediate or inner tube 2606, and a stylet 1812. Theplurality of control rods or wires 2602 ride within the annulus 2610comprised between the outside of the intermediate or inner tube 2606 andthe inside of the outer tube 710.

FIG. 26B illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2620 of a steerable needle or punch. The shaft2620 comprises the outer tube 710 further comprising the lumen 1910. Theshaft 2620 further comprises a plurality of hollow control rods or wires2622, an intermediate or inner tube 2606, and a stylet 1812. Theplurality of control rods or wires 2622 ride within the annulus 2610comprised between the outside of the intermediate or inner tube 2606 andthe inside of the outer tube 710. The hollow control rods or wires 2622can be tubular in configuration and either solid wall or fenestrated,woven, braided, or the like. The inner tube 1606 restrains the controlwires or rods 1606, 2622 radially off-center but does not provide muchresistance against circumferential misalignment.

FIG. 27A illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2700 of a steerable needle or punch. The shaft2700 comprises the outer tube 710 further comprising the lumen 1910 anda solid, full diameter control rod 2702 that is slidably disposed orconstrained within the lumen 1910 with adequate wall clearance such thatminimal friction is encountered but maximum bracing against kinking ofthe outer tube 710 is provided.

FIG. 27B illustrates a lateral cross-sectional view of anotherembodiment of a shaft 2720 of a steerable needle or punch. The shaft2720 comprises the outer tube 710 further comprising the lumen 1910 anda plurality of solid, partial diameter control rods 2722 that areslidably disposed within the lumen 1910 with adequate wall clearance,and comprise gaps or space 2726 from each other, such that minimalfriction is encountered but maximum bracing against kinking of the outertube 710 is provided. The plurality of control rods 2722 can be hollowor solid. They can be fabricated from tubes, and filling the center, orfrom a round, solid bar. The central gap 2726 can be fabricated byslotting a tube or bar or by forming the two parts separately.

FIG. 28A illustrates a lateral (side) view of a distal, deflectableregion 2800 of a steerable needle or punch. The distal deflectableregion 2800 comprises the outer tube 2802, with a first plurality ofradially directed, partial cuts or gaps 2804 oriented in a firstdirection, and a second plurality of radially directed partial cuts orgaps 2806 oriented in a second direction. The gaps 2802 and 2804 areformed in the wall such that not all cuts 2802 are grouped together butare, in at least one case, interleaved with the cuts 2804. The distaldeflect able region 2800 further comprises a first control rod 1802, asecond control rod 1804, and a control rod retainer or keeper 1806, eachseparated by a plurality of slots 1810. The deflectable region 2800further comprises the first weld 2814 and the second weld 2812, whichaxially and radially fix control rods 2806 and 2804 to the outer tube,at a point distal to the flexible region. The two control rods 1802 and1804 are able to separately apply off-center forces on the outer tube2802 and, due to the selective ability of the outer tube to bend in thefirst and second directions, cause the outer tube to flex or articulatein these two directions. The stability of the control rod 1802 allowsthe second control rod 1804 to flex the tube without closing or openingthe gaps 2804 but instead closing or opening the gaps 2806. The samecondition is true for the control rod 1804 stabilizing longitudinalmovement of the outer tube against opening or closing of the gaps 2806in a specific direction so that the control rod 1802 can flex the outertube in the direction of the gaps 2804.

The control rods 1802 and 1804 can be separately affixed to the outertube 2802 distal to the articulating region or they can be affixedtogether and to the outer tube 2802 distal to the articulating region.The control rods can be affixed together, to the outer tube, or to anintermediary structure such as another tube using methods such as, butnot limited to, welding, soldering, fasteners, mechanical interlock,adhesive bonding, and the like. In the illustrated embodiment, the firstcontrol rod 1802 is affixed to the outer tube by the first weld 2814 andthe second control rod 1804 is affixed to the outer tube by the secondweld 2812. These welds 2812, 2814 can preferably be laser welds orsilver soldered joints although the other listed methods can also beused.

FIG. 28B illustrates a cross-section 2820 of the tubing 2800 in thedistal articulating region as viewed in the direction shown. Thecross-section 2820 comprises the outer tube 2802, the central lumen1808, the first control rod 1802, the second control rod 1804, thecontrol rod retainer 1806, and the plurality of gaps 1810.

FIG. 29A illustrates a lateral (side) view of a distal, bi-directionallydeflectable region 2900 of a steerable needle or punch. The distalbi-directionally deflectable region 2900 comprises a first outer tuberegion 2906, with a first plurality of radially directed, partial cutsor gaps 2916 oriented in a first direction, a second outer tube region2904 comprising and a second plurality of radially directed partial cutsor gaps 2914 oriented in a second direction. The cuts or fenestrations2914 and 2816 are formed in the wall such that all cuts or gaps 2914 or2916 are grouped together in their respective outer tube regions 2904and 2906. The distal deflectable region 2900 further comprises a firstcontrol rod 1802, a second control rod 1804, and a control rod retaineror keeper 1806, each separated by a plurality of slots 1810. Thedeflectable region 2900 further comprises the first weld 2908 and thesecond weld 2910, which are located at different axial locations alongthe tubing. The distal end of the outer tubing 2918, located axiallydistal to the deflectable region, is terminated distally by a sharppoint 2920 and affixed to one or more of the control rods 1802, 1804,the control retainer 1806, the distal-most outer tube 2926, or one ormore of these by a fixation point, arc, or ring 2922, which can be aweld, adhesive bond, solder joint, mechanical fastener, integralfabrication, intermediary structure or the like. The two control rods1802 and 1804, affixed to the outer tube at different locationsimmediately distal to their respective articulating regions 2904, 2906by welds 2910 and 2908, are able to separately apply off-center forceson the outer tube regions 2904 and 2906 and cause the outer tube to flexor articulate in these two directions within their specific locations2906, 2904. The stability of the control rod 1802, in both compressionand tension, allows the second control rod 1804 to flex the 2906 tubewithout closing or opening the gaps 2914 but instead closing or openingthe gaps 2916. The same condition is true for the control rod 1804stabilizing longitudinal movement of the outer tube against opening orclosing of the gaps 2916 in a specific direction so that the control rod1802 can flex the outer tube in the direction of the gaps 2914.

The control rods 1802 and 1804 are separately affixed to the outer tubedistal to their respective articulating. The control rods can be affixedto the outer tube, or to an intermediary structure such as another tubeusing methods such as, but not limited to, welding, soldering,fasteners, mechanical interlock, adhesive bonding, and the like. In theillustrated embodiment, the first control rod 1802 is affixed to theouter tube by the first weld 2910 and the second control rod 1804 isaffixed to the outer tube by the second weld 2908. These welds 2908,2910 can preferably be laser welds or silver soldered joints althoughthe other listed methods can also be used.

FIG. 29B illustrates a cross-section 2950 of the tubing region 2904 inthe distal articulating region as viewed in the direction shown. Thecross-section 2950 comprises the outer tube 2904, the central lumen1808, the first control rod 1802, the second control rod 1804, thecontrol rod retainer 1806, and the plurality of gaps 1810.

FIG. 30A illustrates a lateral (side) view of a distal, bi-directionallydeflectable region 3000 of a steerable needle or punch. The distalbi-directionally deflectable region 3000 comprises an outer tube 3006,with a plurality of radially directed, partial cuts or gaps 3008oriented in a first direction, and further comprising a distal end 3010.The distal region 3000 further comprises a hollow tubular control rod3002, a central lumen 3004, a distal weld 3016, a tubing extension 3012optionally terminated by a sharp point 3014, and a hinge region 3020created, in this embodiment, by a cut 3018 in the control rod 3002. Thecuts or fenestrations 3008 are formed in the wall such that all cuts orgaps extend and transect approximately 50% of the diameter of the tube.This transection or cut can range from about 10% to about 90% of thediameter with a preferred range of about 30% to about 70% of thediameter. The transaction can be a simple cut with a rounded end, asillustrated, it can have substantially no rounding, or it can compriseT-slots at the end to facilitate bending depending on the strength ofthe material and resistance to bending. The transection can comprise awidth of about 0.001 to about 0.020 inches with a preferred range ofabout 0.005 to about 0.015 inches and a most preferred range of about0.007 to about 0.012 inches. The control rod 3002 can be affixed to thedistal-most outer tube 3010, distal to any flexibility enhancingfeatures such as the transections 3008, by a fixation point, arc, orring 3016, which can be a weld, adhesive bond, solder joint, mechanicalfastener, integral fabrication, intermediary structure or the like.

This configuration retains the internal lumen as mostly fluid-tight andleak free, except in the region of the hinge cutout 3018 in the controlrod 3002. To prevent leakage through the slots 3008 from the slot 3018,a pressure shroud 3024 is affixed around the exterior of the outer tube.This pressure shroud can comprise, for example, a shrink wrapped orbonded tube of polyester, polyurethane, PTFE, FEP, PFA, or the like. Thewall thickness of the pressure shroud 3018 can range from about 0.00025inches to about 0.010 inches with a preferred range of about 0.0005 toabout 0.005 inches and a most preferred range of about 0.0007 to about0.002 inches. The central lumen 3004 is capable of serving as aleak-free channel for infusion and withdrawal of fluids, both liquid andgas, and can serve as a pressure monitoring lumen, for example, withoutconcern for migration of materials out of, or into, the sides of thedevice.

The hinge 3020, generated by cutting a notch 3018 in the control rod3002 is optional. The hinge 3020 could also be fabricated using morestandard hinge construction comprising a pin and loops or by theinclusion of materials of elastomeric nature to permit flexing. Thepartial lateral cuts can be configured so that a given section of outertube bends more readily in a given direction while another section bendsmore readily in another, preferably orthogonal, direction. In anotherembodiment, the cuts in different directions can be interspersed next toeach other such that a given flexible region can flex in two directionsor planes in the same linear region.

FIG. 30B illustrates a cross-section 3050 of the tubing region 3006 inthe distal articulating region as viewed in the direction shown. Thecross-section 3050 comprises the outer tube 3006, the central lumen3004, the hollow control rod 3002, and the gap 3522 between the controlrod 3002 and the outer tube 3006. The gap 3522 needs to be enough toprevent binding of the control rod 3002 against the outer tube 3006during bending. The gap 3006 can be sized radially between about 0.001and 0.025 inches with a preferred gap of about 0.005 to about 0.020inches, with a most preferred gap of about 0.010 to 0.015 inches.

FIG. 31A illustrates a side view, in partial breakaway, of the distalend of a steerable transseptal needle 3100 comprising an outer tube3112, an inner tube 3106, further comprising a lumen 3108 and a blunteddistal end 3110, a stylet 3102 further comprising a sharp, pointed,distal end 3104, which is shown retracted inside the lumen 3108, acontrol rod 3114, and a keeper or stay 3116. The sharp tip 3104 can beformed integrally to the stylet 3102. The sharp tip 3104 can be conicaland be sharpened to angles ranging from about 10 degrees to about 60degrees from the longitudinal axis, per side. The blunted distal end3110 of the inner tube 3106 can comprise a full round approximatelyequal to the wall thickness, a taper, a chamfer, or the like. The innertube 3106 is small in diameter and is difficult to make completelynon-sharp but it is blunted to the extent possible. The control rod 3114is illustrated and extends within the flexible region of the steerabletransseptal needle. Sufficient space can exist around the stylet shaft3102 and within the lumen 3108 to permit fluids to be injected andwithdrawn or pressure measurements to be taken. In another embodiment,the stylet wire shaft 3102 can comprise one or more longitudinal slots(not shown) to increase fluid flow area therethrough. The stylet wire orshaft 3102 can also have a star shaped cross-section, a C-shapedcross-section, or the like. The sharp tip 3104 is retracted sufficientlyinside the blunted end 3110 that there is no risk of unwanted tissue orguide catheter shaft puncture or damage while the steerable transseptalneedle is being advanced or positioned.

FIG. 31B illustrates a side view of the distal end of the steerabletransseptal needle 3100 with the stylet 3102 advanced beyond the blunteddistal end 3110 of the inner tube to expose the sharp tip 3104. Thesteerable transseptal needle comprises the outer tube 3112, the innertube 3106 with the blunted distal end 3110, the stylet 3102, shownadvanced, further comprising the sharp, pointed, distal end 3104, thecontrol rod 3114, and the keeper or stay 3116. The sharp tip 3104 isadvanced sufficiently to provide for a clean tissue puncture and so thatthe pierced tissue can ride over the stylet shaft 3102, over the blunteddistal end 3110, and onto the outside of the inner tube 3106. Projectionof the inner tube 3106 beyond the outer tube 3112 is traditionally about1.5 cm. This distal projection distance of the inner tube 3106 can bemaintained so that the sharp tip 3104 projects beyond the 1.5 cm or theinner tube 3106 projection can be reduced so that the sharp tip 3104 ispositioned at approximately 1.5 cm (or less) from the outer tube 3112,when the stylet is fully advanced.

FIG. 32A illustrates a side view, in partial breakaway, of the distalend of a steerable transseptal needle 3200 comprising the outer tube3112, the inner tube 3106, the lumen 3108 of the outer tube 3112, theblunted distal end 3110, the stylet 3102 further comprising a neck down3210 to a smaller diameter more proximal stylet shaft 3208, the sharp,pointed, distal end 3104, which is shown retracted inside the lumen3108, the control rod 3114, the keeper or stay 3116, a radiopaque marker3202 further comprising a radiopaque marker lumen 3204, and a radiopaquemarker retainer 3206. The radiopaque marker 3202 can comprise materialssuch as, but not limited to, tantalum, platinum, gold, platinum iridium,or the like. The radiopaque marker 3202 is preferably affixed within thelumen 3108 but can, in other embodiments, be affixed to the exterior ofthe inner tube 3106. The radiopaque marker 3202 can be affixed to thewall of the inner tube 3106, as is, or the inner tube 3106 wall can bemachined to create an increased diameter on the ID or a decreaseddiameter on the OD to accept the radiopaque marker 3202. The radiopaquemarker 3202 can be affixed to the inner tube 3106 by welding, adhesivebonding, swaging, a combination thereof, or the like. In an embodiment,the inner tube 3106 can be formed down to a smaller diameter after theradiopaque marker is installed to prevent the radiopaque marker fromever being dislodged.

FIG. 32B illustrates a side, partial breakaway view of the distal end ofthe steerable transseptal needle 3200 with the stylet 3102 advanced toexpose the sharp end 3104 distal to the distal end 3210 of the innertube 3202. The steerable transseptal needle 3200 comprises the outertube 3112, the inner tube 3106, further comprising the lumen 3108 andthe blunted distal end 3110, the stylet 3102, further comprising thesmaller diameter more proximal stylet shaft 3208, the sharp, pointed,distal end 3104, which is shown advanced and exposed beyond the end ofthe inner tube 3106, the inner tube lumen 3108, the control rod 3114,the keeper or stay 3116, the radiopaque marker 3202 further comprisingthe radiopaque marker lumen 3204, and the radiopaque marker retainer3206. The lumen 3204 of the RO marker 3202 is sufficiently large thatthe stylet wire 3102 can slidably project therethrough with noappreciable drag or binding. The RO marker lumen 3204 should be at leastapproximately 0.002 inches larger in diameter than the OD of the styletshaft 3102.

FIG. 33A illustrates a side view, in partial breakaway, of the distalend of a steerable transseptal needle 3300 comprising all the elementsof the steerable transseptal needle 3200 of FIGS. 32A and 32B, butwherein the sharp pointed end 3104 of the stylet 3102 is replaced by abeveled, sharp end 3302. The beveled end 3302 can be angled at about 10degrees to about 60 degrees from the longitudinal axis of the styletwire 3102. The beveled end 3302 can further comprise one or more facets,not shown.

FIG. 34A illustrates a side view of a stylet hub 3400 comprising theproximal length of stylet wire 3102, the hub body 3402, furthercomprising a hub lumen 3416, a male Luer taper 3414, and a male Luerlock feature 3412, a spring housing 3404, a push cap 3406, a wireretaining tube 3408, a spring 3410, an O-Ring 3418, and an O-ringretainer 3420. The stylet hub 3400 is shown with the push cap 3406 andits spring container retracted, as biased by the spring 3410. The hubbody 3402, the spring housing 3404, the cap 3406, and the O-ringretainer 3420 can comprise plastic such as, but not limited to,polycarbonate, polysulfone, PEEK, PVC, ABS, or the like. The parts canbe assembled using adhesive bonding, solvent bonding, ultrasonicwelding, interference snap fits, or the like. The spring housing 3404slides axially over the OD of the hub body 3402 and these two parts arenot bonded together. The cap 3406 is affixed to the wire holding tube3408 using adhesive bonding, a mechanical interference, or the like. Thestylet wire 3102 can be affixed to the holding tube 3408 using laserwelds, silver solder, crimping, mechanical fasteners, or the like. TheO-ring 3418 prevents fluid leakage through the lumen 3416 into theinterior of the spring housing 3404 where it could escape and causepatient hemorrhage. Air ingress through the lumen 3416 could also leadto an air embolism and thus needs to be prevented by this O-ring. Thespring 3410 can be fabricated from materials such as, but not limitedto, stainless steel, nitinol, titanium, cobalt nickel alloy, or thelike. In the illustrated embodiment, the spring 3410 is an open coil,when relaxed, but could also be a leaf spring or other spring structure.The spring 3410 biases the hub 3400 to keep the stylet 3102 fullyretracted except when activation is required. In the illustratedembodiment, the spring 3410 is fabricated from stainless steel andcomprises an OD of 0.25 inches and a wire diameter of about 0.01 to 0.03inches, with a preferred wire diameter of about 0.015 to 0.014 inches.

FIG. 34B illustrates a side view of the stylet hub 3400 with the springcompressed and the push cap 3406 and its spring housing 3404 fullyadvanced to compress the spring 3410. The stylet hub 3400 comprises theproximal length of stylet wire 3102, the hub body 3402, furthercomprising the hub lumen 3416, the male Luer taper 3414, and a male Luerlock feature 3412, the spring housing 3404, the push cap 3406, the wireretaining tube 3408, a the spring 3410. The stylet wire 3102 is nowadvanced distally due to distal relative motion of the push cap 3406.

FIG. 35A illustrates a side view of a stylet hub 3500 comprising the hubbody 3402 further comprising the Luer lock feature 3412, the male Luertaper 3414, an enlarged diameter grip 3504 around the male Luer lockfeature 3412, the spring housing 3404, the push cap 3406, and a safetyclip 3502. The safety clip 3502 resides within the depression created bythe spring housing 3404 and the enlargement 3504. The safety clip 3502comprises a grip region and a c-shaped section that removably snapsaround the barrel of the hub body 3402. Thus, the C-shape comprisesufficient opening to permit easy attachment and release of the C-clip3502 by grasping the grip region or handle. The safety clip 3502prevents the user from advancing the spring housing 3404 and cap 3406distally. Once the safety clip is removed, the spring housing 3404 andcap 3406 can move distally, under spring compression, to force thestylet shaft 3102 distally. The safety can comprise other structuresthat permit such a safety feature. Such safety features can compriseintegral switches, control knobs, mechanical interlocks, or the like.

FIG. 35B illustrates an oblique view of the stylet hub 3500, comprisingthe spring housing 3404, the Male Luer lock feature 3412, the male Luertaper 3414, and the removable safety clip 3502. The threads forming themale Luer lock feature 3412 can be clearly seen. These threads interlockwith threads on the flange of a female Luer lock connector to form abayonet mount or screw mount to securely maintain attachment. When fullysecured, the hub 3500 or 3400 are positioned precisely with relation tothe hub 3500 or 3400 on the steerable transseptal needle (FIG. 36 ),thus providing for precise locating and function of the stylet tipprotrusion distance.

FIG. 36A illustrates an exterior side view of a steerable transseptalneedle 3600 with its distal end curved 90 degrees. The steerabletransseptal needle comprises the stylet 3102 (not shown because it isretracted), the stylet hub 3500, further comprising the stylet hubbutton 3404 and cap 3406, the safety clip 3502, the flexible region ofthe needle 900, the steerable transseptal needle hub 800, and theblunted distal end 3110.

Note that the stylet hub 3500 can be released and removed from the hub800 of the steerable transseptal needle 3600. Although a Luer lock isshown as the preferred attachment, any type of quick connect can be usedsuch as, but not limited to, mechanical fastener, bayonet mount, screwmount, or the like.

FIG. 36B illustrates the steerable transseptal needle of FIG. 36A withthe safety clip 3502 removed but the activation button 3404, 3406 on thestylet hub 3500 has not been advanced or depressed.

FIG. 36C illustrates the steerable transseptal needle of FIG. 36B withthe activation button 3404, 3406 on the stylet hub 3500 having beendepressed and causing the stylet 3102, and its sharp tip 3104, to beexposed distally beyond the end 3110 of the inner tube.

In other embodiments, the stylet hub can comprise a quick releasefeature for the spring. In these embodiments, when a control button ispushed, an intermediate structure is engaged and forces the stylet shaft3102 distally until a certain point is reached, wherein the intermediatestructure is disengaged and the spring forces the stylet shaft 3102proximally. This disengagement can result from mechanical action thatspreads holding features apart sufficiently to release the stylet shaft3102 and spring 3410. The disengagement can also occur by means of arotary intermediate device that turns such that the stylet shaft 3102and spring 3410 lose engagement and are allowed to be biased proximally.In this embodiment, the stylet sharp tip 3104 is never advanced for verylong and inadvertent advancement of the structure has less risk ofcausing damage to critical tissues because the sharp stylet tip 3104retracts faster than a human can push the device forward.

In yet other embodiments, the hub of the steerable transseptal needlecan comprise a side port that is operably connected to the central lumenof the steerable transseptal needle. This side port can be terminatedwith a female Luer lock and optionally a hemostasis valve or stopcock.This side port can be used to inject or withdraw fluids or to measurepressure while the piercing stylet system is in place and locked ontothe proximal end of the steerable transseptal needle.

FIG. 37 illustrates a top view of a steerable transseptal needle hubbody 3708 affixed to a three-way stopcock 3700. The stopcock 3700comprises a side port 3702 further comprising a lumen (not shown), whichis operably connected to the other lumens of the stopcock through thepetcock 3712, which allows both the side port 3702 and the proximalthrough port 3710 to be operably connected to a central lumen (notshown) of the hub 3708. The ends of the stopcock lumens are preferablyfemale Luer lock ports, but could also be regular threaded mounts, quickconnects, bayonet mounts, or the like. The piercing stylet hub 3500 isaffixed to the Luer threads of the proximal through port 3710.

FIG. 38 illustrates a side view of a faceted sharp distal end 3800 of apiercing stylet 3102. Also illustrated in FIG. 38 are the outer tube3106 and the blunted, generally laterally cut and rounded distal end3110 of the outer tube. The number of facets can range from 1 to 10 ormore with a preferred number of 2 to 4. Where the stylet tip is notfaceted, it can comprise a simple cone or bevel as Illustratedelsewhere. The facets can be cut at an angle of between about and about45 degrees relative to the longitudinal axis of the sty let 3102.

FIG. 39A illustrates a side, partial breakaway view of a steerabletransseptal needle comprising a piercing stylet 3900 further comprisinga distal shaft 3902, the sharp distal tip 3104, a transition zone 3904,a cutout or cutaway section 3908, and a central shaft 3902. Thesteerable transseptal needle comprises the inner tube 3106, the outertube 3112, and the blunted distal end 3110 of the inner tube 3106, andone or more, optional, fenestration, window, opening, or hole 3910 inthe side wall of the outer tube. The cutaway region 3908 can run theentire length of the stylet wire or it can terminate at a transition, asshown, to a substantially, completely rounded distal end 3902. Thecutaway region 3908 can comprise a partial cylinder, hollow or solid,with a longitudinal axis which is general coaxial with the longitudinalaxis of the outer tube, and the inner tube or the several control rodsand keepers, and any liner used in the assembly. The cutaway region 3908can project out the distal end of the inner tube 3106 or it can fullyreside within the inner tube 3106 when retracted, extended, or both.Thus, at least a portion of the stylet may be a partial cylinder, or theentire length of the stylet may be a partial cylinder. The window 3910can permit pressure measurement and fluid injection or removaltherethrough when operably in communication with the cutaway region3908. When an obturator is used in place of the piercing stylet, thestructure of the obturator can be similar, with the exception of thesharp tip, to the structure of the stylet.

FIG. 39B illustrates a lateral cross-section of a stylet wire 3900configured to facilitate fluid flow or pressure measurement while thestylet wire 3900 is in place within the lumen of a steerable transseptalneedle. The stylet wire 3900 has had its cross section reduced thuscreating a half-moon shaped shaft and creating a half-moon shaped lumen3908 within the inner tube 3106. The cross-section can be half-moonshaped, as illustrated, or it can be C-shaped, S-shaped, D-Shaped, Ushaped, or the like.

FIG. 40 illustrates a hub of a steerable transseptal needle safetypiercing stylet wherein the hub of the stylet comprises a quick releaseto actuate, and then retract the stylet. The stylet hub 4000 comprises apush button 4002, a first transmission arm 4004 further comprising afirst magnet 4006, a second transmission arm 4008 further comprising asecond magnet 4010 and a catch 4030, a stylet hub body 4012 furthercomprising a stop 4018, a stylet wire 4016 and a return spring 4014. Thehub 4020 of the steerable transseptal needle further comprises anelectrical connector 4022, operably connected to the inner tubing 4024or its anchor 4026. The outer tubing of the needle is covered with aninsulating jacket 4028.

The stylet wire 4016 is affixed to the first transmission arm 4004.First magnet 4006 is affixed to the first transmission arm 4004 and thesecond magnet 4010 is affixed to the second transmission arm 4008. Thereturn spring 4014 is operably connected to the first transmission arm4004 to bias the first transmission arm 4004 proximally away from thesecond transmission arm 4008. The first 4004 and second 4008transmission arms as well as the spring 4014 reside with, and areradially constrained within a cavity within the stylet hub body 4012.The spring 4014, as well as the first and second transmission arms 4004and 4008 can move longitudinally within the cavity of the stylet hubbody 4012. The spring 4014 is affixed at one end to the stylet hub body4012 and to the second transmission arm 4008 such that the spring 4014,at rest, is uncompressed and distal movement of the second transmissionarm 4008 forces the spring 4014 into compression from which it wants torecover. The spring 4014 can also be used in tension using analternative layout. The stop 4018 within the stylet hub body 4012prevents unwanted distal motion of the second transmission arm 4008because of the stop 4030 interferes with the catch 4030. Thisinterference forces the first and second transmission arms and theirmagnets 4006 and 4010 apart after a predetermined travel.

The magnets 4010 and 4006 can comprise materials such as, but notlimited to, samarium cobalt, neodymium iron boron, iron, or the like.The magnets can comprise magnifier structures to optimize the magneticfields. The magnets can be configured, in a preferred embodiment, sothat opposite poles come together to provide attraction between themagnets, or wherein like poles come together to provide for repulsiveforces.

The electrical connector 4022 is integral or affixed to the anchor 4026or it can be operably connected and affixed to another metal component,such as the jackscrew traveler (not shown). Application of electrical RFpower to the electrical connector 4022 is in electrical communicationwith the inner tube 4024. A separate ground wire can be applied to thepatient. The electrical insulator jacket 4028 is optional but ispreferably affixed around the outer tube for its full length orsubstantially so. Thus the inner tube 4024 ultimately receives the RFenergy and is the component that can burn or cauterize tissue. The innertube 4024 can be blunted, partially, or completely closed off at itsdistal end to render it maximally atraumatic.

The steerable transseptal needle, in other embodiments, can comprisemonitoring systems to measure, display, announce, record, or evaluateoperating parameters of the steerable transseptal needle. In anembodiment, the steerable transseptal needle can comprise strain gaugesto measure the force being applied by the user to bend the needle. Atorque gauge can also be comprised by the system to measure torque beingapplied to the control knob or the torque being applied by the distalcurvature movement. The strain gauge or torque gauge can be affixedwithin the hub or elsewhere within the steerable transseptal needle tomeasure compression or tension forces. This information can be displayedin the form of a readout device, such as a digital display of the forceor torque. The number of turns can be counted and displayed by, forexample, a Hall-Effect sensor, mechanical counter, or the like. In anembodiment, the force or toque can be correlated to the angle ofdeflection at the distal end, the number of turns applied to the controlknob, or both. The readout can be digital or analog and can be affixedto the hub or can be wirelessly received and displayed on externalequipment such as a smart phone, computer, tablet computer, paneldisplay, or the like. The wireless technology can, for example, compriseWi-Fi, Bluetooth®, or other standardized protocols. The human interfacecan, in other embodiments, comprise audible feedback such as a simplebeep or tone, or it can be more sophisticated and provide informationusing language callouts such as force, turns, torque, or the like.

In operation, the system operates similarly to the standard steerabletransseptal needle with a few exceptions. The procedure is to advance asteerable transseptal needle, with a tissue piercing stylet affixed inplace, through a transseptal introducer that has already been placed.The steerable transseptal needle is articulated to generate the propercurve, as determined under fluoroscopic or ultrasound guidance. Thesteerable transseptal needle transseptal introducer assembly iswithdrawn caudally out of the superior vena cava and into the rightatrium of the heart. Proper location, orientation, tenting, and otherfeatures are confirmed. Radiopaque dye can be injected through thesteerable transseptal needle to facilitate marking of the fossa ovalisor blood flow around the distal end of the steerable transseptal needle.Pressure measurements can also be taken through the lumen of thesteerable transseptal needle to confirm tracings consistent with theright or left atrium of the heart. Once proper positioning has beenconfirmed, a safety is removed from the stylet hub and a button on thestylet hub is depressed or actuated to cause the sharpened stylet tip toadvance out beyond the distal end of the steerable transseptal needle.This sharpened stylet punches through the fossa ovalis and the septaltissue pulls over the stylet, over the inner tube, and over theobturator or dilator of the transseptal introducer. At this point, thesharp stylet is released and retracts proximally within the steerabletransseptal needle. The transseptal introducer is now within the leftatrium of the heart and the steerable transseptal introducer can bewithdrawn from the lumen of the obturator.

While the preferred embodiments of the devices and methods have beendescribed in reference to the environment in which they were developed,they are merely illustrative of the principles of the inventions. Theelements of the various embodiments may be incorporated into each of theother species to obtain the benefits of those elements in combinationwith such other species, and the various beneficial features may beemployed in embodiments alone or in combination with each other. Otherembodiments and configurations may be devised without departing from thespirit of the inventions and the scope of the appended claims.

We claim:
 1. A method of crossing an atrial septum of a patient, saidmethod comprising: providing endoluminal punch comprising: an outertube, said outer tube characterized by a distal end, and proximal end,and an outer tube lumen extending from the distal end to the proximalend thereof, said outer tube having a flexible region near the distalend of the outer tube; a first control rod disposed within the outertube, said first control characterized by a distal end and a proximalend, said first control rod comprising a partial hollow cylinder,wherein the first control rod is longitudinally fixed to the distal endof the outer tube and extends proximally to the proximal end of theouter tube; and a second control rod disposed within the outer tube,said second control rod characterized by a distal end and a proximalend, said second control rod comprising a partial hollow cylinder,wherein the second control rod is longitudinally fixed to the distal endof the outer tube and extends proximally to the proximal end of theouter tube; an inner tube, disposed within the outer tube lumen, withthe first control rod and second control rod disposed between the innertube and the outer tube, said inner tube having a sharpened distal tipextending distally from the distal end of outer tube; at least onekeeper disposed circumferentially between the first control rod andsecond control rod and disposed between the inner tube and the outertube; and an RF energy source operably connected to the inner tube,wherein the inner tube is operable to conduct RF energy from the RFenergy source to a tissue within a body of a patient; and navigating thesteerable endoluminal punch through a vasculature of the patient tolocate the sharpened distal tip of the inner tube against the atrialseptum of the patient; applying RF energy through the inner tube to theatrial septum; advancing the inner tube through the atrial septum into aleft atrium of the patient.
 2. The method of claim 1, further comprisingthe steps of: Advancing a distal end of guide catheter and a distal endof an obturator and/or dilator, across the atrial septum until thedistal end of the guide catheter resides within the left atrium; andWithdrawing the obturator and/or dilator along with the steerableendoluminal punch from the left atrium and from the guide catheter toallow for catheter placement through the guiding catheter.
 3. A methodof crossing an atrial septum of a patient, said method comprising:providing endoluminal punch comprising: an outer tube, said outer tubecharacterized by a distal end, and proximal end, and an outer tube lumenextending from the distal end to the proximal end thereof, said outertube having a flexible region near the distal end of the outer tube; afirst control rod disposed within the outer tube, said first controlcharacterized by a distal end and a proximal end, said first control rodcomprising a partial hollow cylinder, wherein the first control rod islongitudinally fixed to the distal end of the outer tube and extendsproximally to the proximal end of the outer tube; and a second controlrod disposed within the outer tube, said second control rodcharacterized by a distal end and a proximal end, said second controlrod comprising a partial hollow cylinder, wherein the second control rodis longitudinally fixed to the distal end of the outer tube and extendsproximally to the proximal end of the outer tube; an inner tube,disposed within the outer tube lumen, with the first control rod andsecond control rod disposed between the inner tube and the outer tube,said inner tube having a distal tip extending distally from the distalend of the outer tube; a stylet disposed within the inner tube, saidstylet having a distal end and being slidably disposed withing the innertube such that the distal end extends distally from the distal end ofthe inner tube; at least one keeper disposed circumferentially betweenthe first control rod and second control rod and disposed between theinner tube and the outer tube; and an RF energy source operablyconnected to the stylet, wherein the stylet is operable to conduct RFenergy from the RF energy source to a tissue within a body of a patient;and navigating the steerable endoluminal punch through a vasculature ofthe patient to locate the distal tip of the stylet against the atrialseptum of the patient; applying RF energy through the stylet to theatrial septum; advancing the stylet and inner tube through the atrialseptum into a left atrium of the patient.
 4. The method of claim 3,further comprising the steps of: Advancing a distal end of a guidecatheter and a distal end of an obturator and/or dilator, across theatrial septum until the distal end of the guide catheter resides withinthe left atrium; and withdrawing the obturator and/or dilator along withthe steerable endoluminal punch from the left atrium and from the guidecatheter to allow for catheter placement through the guiding catheter.5. The method of claim 3, wherein the inner tube has a blunt distal tip.